Why I Challenge Myself with a Side Hustle Even After Earning Over 10 Million Yen: How to Design a Rich Life Through 'Main Job x X Monetization' Even Starting in Your 40s

How would you feel if you were asked, “Is a side hustle really necessary even with an annual income of 10 million yen?”
What would you think?

Many might think, “If you’re earning that much, isn’t that enough?”

Actually, I thought the same way until I turned 40. I had reached an annual income of 10 million yen and my family life was stable. I felt, “Is there really any need to increase my income beyond this?”

However, once I entered my 40s,
these anxieties began to weigh on my mind.

It was during a time when I was harboring such vague anxieties that I encountered a side hustle utilizing social media (X), and my life changed completely.

I originally had a stable income as a company employee, but once I increased my income sources through a side hustle, I gained not only “money” but also benefits beyond my imagination, such as “self-affirmation,” “career expansion,” “synergy with my main job,” and “peace of mind for the future” one after another.

In this note, I, having exceeded an annual income of 10 million yen, will share based on my own experience:

I will convey these themes based on my actual experiences.

Regardless of your age or current annual income, “a way of life that does not rely solely on your main job” and “how to gain peace of mind for the future through a side hustle” I hope this note will be the trigger for those who want to know to take a step forward.

So, let’s start right away with the reason why I decided to start a side hustle.
I will talk about that reason first.

1. [Even with an annual income over 10 million yen] Why is a side hustle absolutely necessary?

“If you’ve reached an annual income of 10 million yen, shouldn’t you just be satisfied with maintaining the status quo?”

I used to think that way too. Certainly, financially, I might not be in trouble for the time being.

However, after entering my 40s, I suddenly realized something.

“Should I really continue to entrust my future solely to my main job…?”

(1) Things that cannot be obtained through “financial stability” alone

An annual income of 10 million yen looks like a sufficient income on paper. On the other hand, after reaching that point, a sense of stagnation began to emerge, wondering, “Is it okay to stay like this?”

Although my main job is stable, if I settle for the status quo, I neglect to expand my new skills and personal connections. The fear of spending years or decades without expanding my career path was always somewhere in my heart.

(2) There are few adults around who continue to 'grow'

What I realized painfully is the fact that once you pass your 40s, “adults who actively seek growth” decrease drastically.

When people with an annual income of 10 million yen or more gather, there is often an atmosphere of “I’ve already done enough.”

However, there are many people in their 40s and 50s in the world who continue to grow and raise their stage through activities outside of their main job.

It was only after being inspired by such people that I realized, “It is precisely because I have my current income that I can take on new challenges.”

(3) The 'skill multiplication' that side hustles bring

What I chose as a side hustle was information dissemination using SNS (X).

At first, it was a hobby-like theme that had “nothing to do with my main job,” but eventually it shifted little by little toward monetization. In that process, I learned know-how for marketing, branding, and self-promotion. These are skill sets not found in my main job, and are, so to speak, “another weapon.”

The interesting thing is that when I returned the weapons gained from this side hustle to my main job, it was also useful for career advancement and team management.

As a result, my evaluation in my main job went up, and my income increased even further.

(4) Relying only on your 'main job' narrows your perspective

Even if you are in a high-paying job, if your perspective remains only within that industry or organization, it could end up narrowing your future possibilities.

When you come into contact with different communities and industries through a side hustle,
you can make unexpected connections and gain new ideas.

I believe that such “expansion” is the secret to continuing to grow even from your 40s.

(5) A side hustle to aim for 'growth beyond stability'

Of course, it is true that there is a large element of risk hedging, such as worrying about company performance or fearing the evolution of AI.

However, what I feel most strongly is that
“a side hustle is a powerful engine to update yourself.”

If you are earning over 10 million yen a year and feel “satisfied with the status quo but somehow unfulfilled,” a side hustle as a place for growth and challenge should help push you toward your next step.

2. [What was supposed to be a hobby changed my life] The story of how X dissemination changed my destiny

I mentioned the reason I started X in my previous note, but I would like to explain it in more detail once again.

(1) Why I started X

I started X (then Twitter) on December 18, 2020.

Just as the fury of COVID-19 was beginning to subside, economic activity had not yet returned to normal, and it was a period when my own work at the company was slightly relaxed.

At that time, I happened to receive advice from an acquaintance who said, "You've turned 40, so you should start thinking about asset formation in earnest," so I decided to start "Tsumitate NISA," which allows beginners to invest with small amounts.

That said, I had no investment knowledge whatsoever.
First, I bought up books for investment beginners at BOOKOFF and diligently read them to input knowledge.

At the same time, thinking, "I still need to get the latest information..." and while exploring what would be good on the internet, I set my sights on X (Twitter) for its fast information speed, and creating an account and logging in immediately was the reason I started using SNS.

Of course, at first, information gathering was the main thing, so I was purely a lurker.

(2) My first post had zero reaction... The reason I continued anyway

One day, I found the idea in a book that "knowledge is better retained if you output it, not just input it," and I decided to put it into practice immediately.

I decided to start the task of posting (outputting) the information and knowledge I had learned (inputting), without directing it at anyone in particular.
Just doing it casually and slowly.

With a light heart.
Of course, 0 likes, 0 replies.

There wasn't a single person who reacted.

(3) My first viral post born from being fueled by an "inferiority complex"

Here, a change occurred in my state of mind.

Moving from being a lurker to a poster, I began to see various creators (influencers).

・People who have been actively managing assets since they were young and have abundant knowledge and experience
・People who are investing tens of millions of yen
・People who are in their 20s but already have tens of millions of yen in savings and assets

Compared to them, as for me...

That's right, a complete inferiority complex.
Honestly, I felt quite down... I felt embarrassed doing it...

That said, it is also true that I started this for myself and for my family.
One day, I posted these conflicting thoughts as a 'scribble'.

Then,
this unexpectedly went viral!?

I received reactions from many users.

"I thought beginners shouldn't post, you gave me courage!"
"I'm also investing from age 45, I'm happy to see someone of the same age with the same thoughts!"
"Thank you for speaking for me, I'm rooting for you!"

This is it!

At the time, there were many influencers in the money and investment space.
But most of them were veteran investors.

"There are many veteran investment influencers, but... aren't there no 'beginner' investment influencers!? Is this... an open position!?"

From here, I graduated from being just a lurker or a casual poster,
and decided to start posting on X in earnest and managing it to grow.

(4) The wall of 'I can't make money...' even after followers surge

After I started managing it, my overwhelmingly differentiated branding paid off, followers increased by 1,000 every month, and I reached 10,000 followers in the 10th month since account registration.

After that, I registered for an online salon for X management,
reviewed my self-taught management methods, and started managing based on correct logic to give it a boost.

I was able to grow to 35,000 followers in 2 years.

However...
I wasn't monetizing at this time, to be precise, I didn't know how to monetize and couldn't do it.

And coupled with a major algorithm change,
the days of follower growth gradually slowing down continued.

"What... am I doing X for?"The question grew bigger day by day.

Waking up early in the morning to think about posts,
and spending a lot of time interacting with other accounts.

It's fun, but for some reason, it's painful...

Perhaps this feeling sprouted because "I wasn't receiving any compensation".

So this time, I decided to start learning 'SNS monetization'.
This became my full-scale entry into a side hustle.

That was in January 2023.

3. [Realization] 3 Reasons Why I'm Glad I Started a Side Hustle

Starting a side hustle has become an increasingly important option for modern career development and, in a broader sense, for life planning.

Not just for those in their 20s and 30s, but also for employees in their 40s and older,a side hustle is a means not only for financial stability and future preparation, but also for self-actualization and expanding new possibilities.

I will explain in detail from three perspectives why I am glad I started a side hustle over the past two years (though I've been on X for four years, I've been monetizing for two).

(1) No one can predict the future of a company

The modern business environment is full of uncertainty.
No matter how large a company is, risks such as bankruptcy, unpaid wages, and layoffs always exist.

It is no longer rare for super-excellent, well-known large companies that had TV commercials you often saw when you were a child to be bought out by foreign capital and cease to exist.

Economic crises, like the past Lehman Shock or the COVID-19 pandemic that occurred a few years ago,can suddenly strike companies and completely change the lives of their employees.

An acquaintance of mine also lost his job at 41 when the large JTC he had worked at for many years suddenly went bankrupt.

He struggled greatly to find re-employment, and since he had a family, he faced significant financial anxiety.

From cases like this, I feel that in this Reiwa era,
there are limits to a 'way of working that relies solely on a company'.

Furthermore, the future of the pension system is also opaque.

With discussions about raising the age to start receiving benefits and reducing the payout amounts,
relying on the company or the government for retirement funds is clearly high-risk.

If you can secure a new source of income by starting a side hustle, it becomes a safety net to prepare for such unforeseen circumstances, allowing you to protect yourself.

By starting a side hustle, I have also built a situation where I can sustain my life for a while even if something happens.

This is truly huge for me mentally in terms of living!

(2) Is the 'Era of Everyone Having a Side Hustle' coming in 5 years?

The COVID-19 pandemic significantly changed how we work.

With the spread of remote work, working styles that are not bound by time or place have become common, andthe hurdles for side hustles have also dropped significantly.

Already,many companies are accepting, and even encouraging, side hustles as we see a trend toward that.

My company has also established a policy to lift the ban on side hustles, and the number of colleagues starting their own side businesses is growing rapidly.

Side hustles are no longer something for a select few, but are becoming a standard option for company employees. I believe this trend will only accelerate with each passing year.

And I genuinely believe that five years from now, side hustles will become even more generalized as part of career development.

By acquiring new skills and expanding your network through a side hustle, you can also have a positive impact on your main job.

I have already made my start, but in preparation for the coming era where everyone has a side hustle, it is essential to prepare and take action now, regardless of your age
.

(3) People in their 40s and 50s are the ones who need a 'second income source'

The period from your 40s onwards can be called a turning point in life.

As retirement approaches and physically demanding work becomes more difficult, anxiety about your family's future and retirement funds increases.

It is also a time when financial burdens become heavier, such as
children's education expenses, mortgage repayments, and caring for aging parents.

In such a situation, many people likely feel that relying solely on a salary from their company is precarious.

I started my side hustle at the age of 43.

At first, I struggled and found it difficult to monetize, but
even so, as I continued to try and fail without giving up, results gradually began to appear,

and now I am able to earn an income from my side hustle that is comparable to my main job.

From this experience, I am convinced that
'it is never too late to start a side hustle, even in your 40s or later'.

In fact, the age range of people starting side hustles is broad,
and there are many cases of success not only among those in their 20s and 30s, but also in their 50s and 60s.

I am truly glad that I didn't give up on my side hustle back then by using my age as an excuse.

You can have a side hustle at any age and in any environment.

Let's turn the situation you are in into a 'trigger' rather than an 'excuse.' Let's do a side hustle!

4. [Shocking] Side hustles and your main job do not conflict! The reason why they actually create an explosive synergy

Many people might think that it is difficult to balance a side hustle with their main job.

However, in my experience,
far from putting pressure on my main job, a side hustle created a 'synergy' that mutually enhanced both.

In fact, my annual income from my main job has increased significantly since I started my side hustle, as shown below!

The business skills and peace of mind I gained from my side hustle boosted my performance in my main job.

(1) Self-esteem increases tremendously

A side hustle is a valuable opportunity to produce results through your own efforts, rather than relying on a company's reputation.

I started my SNS side hustle, mainly on X, after I turned 43.

When I earned my first few thousand yen, I felt a strong sense of achievement, thinking, 'I can actually do this too!!!!'

This success experience has
value beyond just the income.

Every time I achieve results in my side hustle, my self-esteem—the feeling that 'I did it!'—soars, which significantly improves my motivation in my daily life and main job.

For example, in my main job, I used to be passive and lacked confidence during presentations and proposals.

However, the experience of receiving high praise from clients in my side hustle led to the confidence that
'I can do it,' and I became able to express my opinions proactively.

As a result, my credibility within the team increased, and I had more opportunities to be selected as a project leader.

My annual income also exceeded 10 million yen after starting my side hustle,
leading to a virtuous cycle in my career where success in my side hustle boosted my self-expression in my main job.

(2) You can be bold because you have a secondary income

Side hustle income provides peace of mind as a financial safety net.

Since I started earning from my side hustle, I have developed
a sense of security that 'even if something goes wrong in my main job, I can still make a living.'

This peace of mind has significantly changed my challenging spirit in my main job.

Previously, I tended to act while worrying about the reactions of my boss and those around me.

However, having side hustle income allowed a mindset of 'it's okay if I fail' to take root,
and I became able to act proactively.

For example, when I made a bold proposal to review conventional methods for a new company project, it was adopted and achieved great results. This is an area I would never have stepped into before.

This track record was recognized, and I was promoted to an executive position.
At that time, my annual income jumped from 12.1 million yen to 17 million yen.

The financial and mental leeway provided by my side hustle enabled me to take risks in my main job, which directly led to career advancement (raises and promotions).

Anyway, my mental strength became incredibly tough after I started my side hustle.
I became confidently bold to an amusing degree (laughs).

(3) Is 'I have no time' just an excuse? The ironic result of increased efficiency

To start a side hustle, you need to use your limited time effectively.

I decided to secure one full day out of the five weekdays for my side hustle, and I seriously committed to improving the efficiency of my main job.

For example, I turned the creation of meeting materials into templates and clearly set priorities for tasks.

I reduced unnecessary overtime and cut my work hours by about 20%.
Surprisingly, by increasing efficiency, I improved the quality of my work and gained the byproduct of higher evaluations from my colleagues.

The efficiency measures I started to carve out time for my side hustle ironically accelerated my success and evaluation in my main job
.

The phrase that symbolizes my experience is,
'If you want to do a side hustle, you should actually work harder at your main job'.

To succeed in a side hustle, time management and setting priorities are essential.
Those skills are directly applicable to your main job, which ultimately led to promotions and raises.

A side hustle and a main job create a virtuous cycle that enhances each other.

5. [Many Side Hustles] 3 Reasons Why I Still Choose X Monetization

When you hear 'side hustle,' what kind of work comes to mind?

Reselling, product sales, blogging, web writing, live chat, point sites, survey monitoring, handmade sales, selling/reselling used goods, video distribution like YouTube, video editing, food delivery...

These side hustles differ depending on their type, but
they require initial investment, take time to acquire skills, or require a huge amount of time investment....

The monetization using X that I do certainly has disadvantages as well as advantages.

Nevertheless, I truly recommend it.
I have listed three reasons.

(1) Almost zero cost! It doesn't hurt if you fail

Anyway, when starting something new, I think it is very important to start with as little initial investment as possible.

To put it extremely,
if there is 'zero initial investment,' you can start easily, and even if it doesn't go well, you can make the decision to withdraw immediately.

In that regard, monetization on social media, especially monetization centered on X, has the appeal that
initial costs are extremely low and the barrier to entry is low.

For example, a side hustle in product sales incurs significant initial inventory costs, and
YouTube streaming requires filming equipment and editing software.

Since X monetization is primarily based on 'text,'
all you need is a smartphone and an internet connection.

There is no need to purchase special equipment or paid tools, and
the initial investment is almost zero (though I would like you to join the X Premium plan if possible).

Furthermore, creating an account and posting are of course free, and
you can start by simply honing your writing skills and sense for sharing information without needing specialized skills.

Even if you don't get results,
there is no financial loss, and the risk other than time is extremely low.

Also, beyond financial costs,
there is an advantage in terms of time costs.

Even with the same social media, YouTube requires a significant amount of time for video editing, and
Instagram also requires time for editing the photos you've taken.

On the other hand,
since X is text-based, you can easily type it out on your smartphone whenever and wherever you think of it.

You don't need to stare at a computer for two or three hours, and
you can effectively utilize your spare time to generate revenue.

For those who want to keep initial costs as low as possible, or those who have time constraints and want to do a side hustle in their spare time, X monetization is absolutely perfect.

(2) Explosive reach! Increase your popularity overnight

The greatest strength of X lies in the platform's unique 'reach' (diffusion power).

Through repost and quote repost features,
high-quality posts have the potential to reach many users in an instant.

For example, while it takes time for content to be searched on YouTube or blogs, on X, it is not a dream to gain tens of thousands to millions of views in a short period if a single post goes viral.

Even for beginners, if you post content that captures trends or resonates with people,
you can rapidly increase your awareness even from zero followers.

In fact, on X, cases where general users attract attention overnight are frequently seen, and the low barrier to diffusion is a characteristic.

Furthermore, it is unique to X that you can expect further diffusion through reposts by influencers with many followers.

I believe it is a major advantage that there are equal opportunities for beginners, the growth speed is fast, and
consequently, early monetization can be expected.

A side hustle that allows you to earn your first profit in 2-3 months and achieve a monthly income of over 100,000 yen within a year with a high probability is quite rare, isn't it?

(3) Wide range of monetization! Multiple pillars on a single platform

X monetization has a wealth of monetization options, and its strength lies in the ability to flexibly increase income sources according to your skills and follower count.

For example, it offers a wide range of possibilities, from basic methods like ad revenue from X Corp and affiliate marketing where you introduce company products or services, to fixed compensation from companies for PR projects, selling your own digital content (note, Brain, Kindle...), and even online schools and consulting until the possibilities are vast.

While product sales and handmade goods require time and cost for production and inventory management,
many projects on X can be completed just by posting, making it efficient.

While investments and delivery work tend to rely on a single source of income,
on X, you can diversify risk and build a stable side income by combining multiple revenue routes.

In this way, X monetization allows you to step up gradually from beginner to advanced levels, and it is an attractive side hustle where long-term revenue growth can be expected.

6. [Before You Start] 3 Points to Master for Side Hustle Success

(1) “Self-study is a detour”: The importance of buying time with money

While it is possible to start a side hustle through self-study, there is a risk that it will be inefficient and take too much time.

I also started by managing X through self-study, but looking back now, I regret not following a mentor and learning while managing it, as I could have reached results faster.

Common goals on X are 10,000 followers or 100,000 yen in monthly income from X side hustles, but from my experience, if you proceed through trial and error on your own, I think it will take at least 3 years.

However, if you learn the correct knowledge and know-how from a professional in the field, you will likely be able to
achieve the same goal in 6 months to 1 year.

This time difference is equivalent to
'saving 2 years' worth of opportunity cost'.

Collecting free information is useful, but fragmented knowledge often leads to detours.

By learning systematic know-how from paid courses or a reliable mentor, you can master the understanding of algorithms and tips for effective posting in a short period.

What is important is the mindset of 'buying time with money'.

Because a side hustle is something you work on in limited time, it is important to prioritize efficiency and have a strategy to produce results early.

(2) The difference in results is like heaven and earth depending on 'who you learn from'

The success of a side hustle is greatly influenced by who you learn from.
It is no exaggeration to say that this is everything.

To be honest,
I have alsoexperienced both success and failure in choosing who to learn frommyself. Well... I'll leave it at that (laughs).

As a piece of advice,
first,you should choose someone who has been consistently achieving results both in the past and present.

Because X's algorithms and trends change frequently,
past success stories alone may not always be applicable.

People who are currently active
have the ability to adapt to environmental changes and can provide the latest know-how.

Whatever you do, avoid people who only use 'past glory (achievements)' as their calling card.

Next,someone who has experienced hardshipis superior in that they
can understand the stumbling blocks and anxieties of beginners and provide practical advice.

For example, the stories of hardship from someone who started with zero followers and failed many times before finally succeeding are packed with reproducible tips.

Also, someone with 'many years of experience' has more 'drawers' of knowledge than you might imagine to handle algorithm changes and market fluctuations, so you can expect guidance tailored to various situations.

When choosing a reliable mentor, checking the transparency of their achievements and their teaching style to find someone who suits you is the shortcut to success in your side hustle.

(3) You won't get discouraged if your roadmap is clear

What is necessary to achieve any goal is
the 'ability to draw a clear roadmap'.

By breaking down your goals into specific timeframes, such as 'what you want to become by when,' it becomes easier to manage your progress.

For example,
set a goal for X operation as '10,000 followers and 100,000 yen in monthly income in one year'.

Then,
you can see how many followers you should have and how much monetization revenue you should be making halfway through at 6 months.

Furthermore, at the halfway point of 3 months, and then at one-third of that at 1 month...
it gets broken down, and as a result, 'what you should do right now' becomes clear.

However, even if you can draw this roadmap,if it is not drawn 'correctly,' you will end up walking the wrong path and taking a detour to reach your goal.

Creating a roadmap by yourself
is extremely difficult for beginners, as setting goals and judging priorities is hard.

If possible,
borrow the power of an experienced mentor.

It provides concrete steps to reach your goals, preventing wasted effort.
It reduces hesitation and allows you to focus on taking action.

A roadmap serves as a guide to maintain the motivation to continue your side hustle and steadily accumulate results.

By the way, I
can draw up your roadmap!

7. [Summary] A Second Income Source Enriches Your Future and Your Heart

(1) Too late? It is absolutely not too late to start in your 40s

Thinking 'it's too late for a side hustle' in your 40s is a huge misunderstanding.
I want to say this loud and clear.

Because I started my own SNS side hustle at 43.
Whether you are in your 20s, 30s, 40s, or 50s, age is irrelevant.

In fact, because we live in an era where we cannot fully rely on our companies,
regardless of age, a side hustle becomes a hedge against life's risks.

To repeat, I started on X at 43 and was able to achieve the results mentioned at the beginning.
Leveraging 25 years of professional experience,

if you start posting on X, you will experience the moment your hobbies and knowledge turn into income
.

It is a chance to open the door to a new career while firmly protecting your livelihood with your current main job.

If you take a step to test your potential while maintaining the security of being a 40-something employee, your future will expand beyond your expectations.

Age is not an excuse, but a strength and a trigger to start something.
By taking action now, you can build a life that your future self three years from now will thank you for.

(2) The shocking virtuous cycle where a side hustle accelerates your main job

Far from hindering your main job, a side hustle is a trump card that creates surprising synergy.

Every time you post on X and see your followers and earnings increase, you experience a sense of accomplishment and your self-esteem rises.The confidence that you have accomplished something on your own bubbles up.

This energy spills over into your main job, leading you to present bold ideas in presentations and projects, and positively influencing how you navigate within the company.

It plants the conviction that 'I can do it!',
leading to support for higher annual income and improved status in your main job.

In fact, it is said that people who earn 50,000 yen a month from a side hustle often secure promotions and raises in their main jobs as well.

Before giving up by saying 'I don't have time,'
why not start with one post a day?

The virtuous cycle where your side hustle and main job enhance each other will become the engine that makes your life shine.

(3) I Recommend X (Twitter) Monetization

As I have said repeatedly,
among the many side hustles available, 'X Monetization' is the ideal form of low-risk, high-return work.

You can start with zero initial investment,
and by simply posting about your hobbies or knowledge using just one smartphone, you can generate income.

I myself was able to pave the way to 100,000 followers and a 7-figure monthly income by first sharing my knowledge of financial investment, and later by posting about business hacks and my views on work.

With the viral power of X,
even a beginner can have a single post go viral, leading to a moment that changes their life.

There are plenty of monetization options, such as affiliate marketing and corporate PR.
Even if you fail, there is no financial risk, and you are left only with the lessons learned.

This ease of entry and immense potential is something hard to find in other side hustles.

If you post about what you love and what you are good at on X, the day will surely come when it grows into a second source of income. Come on, take the first step today and seize a free and prosperous future!

8. For those who want to know more

(1) [True Story] How My Life Changed After Starting X at 43: Until Achieving 100,000 Followers & 7-Figure Side Hustle Income

In this article, I candidly reveal the process of how I started from 0 followers on 'X (formerly Twitter)', achieved 100,000 followers, and reached a 7-figure side hustle income.

I have packed it with real-life experiences, including the specific strategies I implemented, the points where I stumbled, and how I made a V-shaped recovery from there.

I think you will be able to get a concrete image that 'maybe I can do this too!', so please use it as a reference.

Click here for details
↓↓↓

(2) LINE for Individual Consultations (Limited to the first 5 people)

'I want to earn a stable ○○,000 yen per month from a side hustle'
'I want to grow my X account and seriously monetize it'
For those people, I have prepared a free consultation session.

I will resolve these concerns one by one,
and together we will think of the shortest route tailored to your situation.

This is a one-on-one ZOOM meeting,so please feel free to ask anything.

[How to apply for a meeting]
1. Send 'Meeting Request' to the LINE below
→ https://lin.ee/CSZsurM

2. After confirmation, I will contact you to schedule a date
3. Conduct a one-on-one meeting via ZOOM

However, the free slots are limited to[the first 5 people each month].

If you are even slightly interested,
please send a message as soon as possible.

Let's succeed in 'X Monetization' together and take a step toward your new future!