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I Built My Multimillion-Dollar Side-Hustle While Working a Full-Time Job and So Can You

Juggling a side hustle alongside a full-time commitment will stretch you in every way possible, but the rewards are even more fulfilling.

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According to estimates, more than 44 million Americans have a side hustle. You can see why. Side hustles are a low-risk way to earn extra cash or explore a passion -- and there's always the chance they could become full time.

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I launched mine in 2015 alongside my full-time job as a petroleum engineer. Back then, I had $50K of student debt, a long distance relationship and parents who needed my support. I wanted more freedom, money and control in my life, so I bought a few courses and taught myself how to sell products online.

Within 11 months, my side hustle was generating more than $250K a month. Last July, I quit my corporate job, closed the gap with my girlfriend and became a full-time entrepreneur. Part of this success was due to a good product choice in a vibrant market. An even bigger chunk was because of the habits, disciplines and mindsets I adopted along the way.

These are the four core principles that helped me build a successful business quickly while working a full-time job. Use them as you launch your side hustle to maximize your chance of success.

1. Build your focus muscle.

Time is your biggest obstacle when running a side hustle. With eight or nine hours spent at your day job, building a side hustle might seem impossible, but it isn't. Instead, transform "no time" into a huge advantage by forcing yourself to get productive with your limited time.

Focus is a skill you can develop and train -- just like anything else in life. Combine high focus with prioritization and you'll become more effective. Eventually, you'll accomplish more in an hour than you used to in a day. Here's what you can do to make this a reality:

First, plan tomorrow, today. You have a finite tank of focus and willpower, so you've got to use it wisely. It's a waste of valuable time deciding what to do at the start of each session. Creating a plan the night before so you can start straight away will make you more productive.

Next, ensure you're always working on the most important thing by choosing just one thing to get done. When you focus on executing one thing, the small stuff becomes irrelevant. Maximize your time by leveraging the top priority, highest impact tasks.

Finally, don't allow perfectionism to become another form of procrastination. Once you feel you're 90 percent there, move on to the next thing -- 90 percent is still an A.

Related: The Unexpected Benefits of Walking the Harder Path

2. Cultivate rituals for consistency.

How far and fast you go with your side hustle depends on your habits and your ability to focus on the right things.

It's much better to work on your business for 30 minutes a day than to cram everything into a single session on a Saturday. Working a little every day allows you to build momentum and accumulate skills that get better over time. When I was building my side hustle, I scheduled my second "work day" between 6 p.m. and 8 p.m. and treated it as seriously as my real job. Over time, my mind associated evenings with focused work. My output started to increase.

What you do consistently determines your results. Ask yourself: are your daily commitments aligned with what you want to achieve? It's easy to justify why you can't work on your side hustle, but when work sessions become a daily ritual, you can leverage your calendar to keep you accountable to your goals.

Related: 50 Ideas for a Lucrative Side Hustle

3. Brainwash your subconscious.

When I started my side hustle, I had no idea if it was going to be successful. I had passion and drive, but no business experience or belief in myself to break away from societal norms.

I wasn't born an entrepreneur, so I had to brainwash myself into believing I could be one. You have to; because the world will happily convince you otherwise. There's so much negativity out there that if you don't train yourself to think you're bigger and better than your present circumstances, you never will be.

In addition to reading books, practicing a morning routine and taking consistent action, I transformed my bathroom into a fortune cookie by pinning up my goals, positive quotes and pictures of things I wanted to have to create a subconscious daily reminder of them. I filled my downtime with positive audio, listened to podcasts during my commutes and set up my social media feeds to only see motivational and inspirational content. I even started telling people I was an entrepreneur instead of an engineer, which changed how I thought and behaved around others.

You'll find it difficult to break out of the employee mindset unless you cultivate an entrepreneurial belief system. You'll struggle to take risks, step out of your comfort zone and deal with the inevitable setbacks. You'll also struggle to retain success -- even when you do achieve it. Brainwashing myself to believe I was an entrepreneur became the number one catalyst for my success.

Related: Cultivating The Mindset of a Successful Entrepreneur

4. Accelerate your learning.

In the early stages of running a side hustle, don't try to figure it all out yourself. It'll take you longer, cost you more and discourage you from trying again if you fail because you haven't built up the resilience to handle losses yet. There are proven methodologies to help you get your first sales, so fast-track your success by choosing a mentor and following their advice.

We live in an incredible time where we have unprecedented access to mentors, courses, coaches and frameworks. I paid $2,500 for my first course to learn how to sell products online. It shaved years off my learning curve. Once I realized the power of learning from the right coaches, I stopped maxing out my retirement funds and invested in mentors -- which further accelerated my path to success.

Once you win through someone else's guidance, you'll get excited to discover what else you can do -- and you won't be able to stop learning and investing in yourself.

Building a side hustle goes beyond money

Building a successful side hustle will change your life thanks to the new experiences, insane personal growth, and freedoms that come from being your own boss.

But it's tough. Juggling a side hustle alongside a full-time commitment will stretch you in every way possible. It's the harder path, but thanks to the obstacles you'll be forced to overcome, the rewards are even more fulfilling.

So if you're ready to build a side hustle, go for it. Invest your time and energy in these four fundamentals and use your business as a vehicle to stop settling and create the life you want.

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