By any definition, becoming a millionaire by your 30s isn’t easy, unless you happen to come from a lot of money. Tips abound on how you can accumulate wealth through saving and smart investments, but unless you’re putting away a lot of cash, a seven-figure net worth at such a young age can seem like a pipe dream.

But it is attainable, at least if you’re resourceful, driven, and of course, lucky enough. While millennials have gotten a reputation for being entitled, many in their cohort have proven exactly how flexible, creative, and ultimately successful they can be in the business world. In some cases, they’re redefining what success looks like, all while pulling in massive incomes. We talked to two millennials who have achieved millionaire status about what it took to get there—and the wisdom they have to share.

Find the ideal ‘side hustle’

Entrepreneurship is highly prized in American society, but it can often seem vague and unattainable. Knowing what it actually involves and forming a strategy can make all the difference.

Grant Sabatier, founder of Millennial Money, more or less fell into it. His “aha moment” came when he started his first freelance project. “I was working full-time at a digital marketing agency and had only been there about three months when I sold my first side-hustle gig,” Sabatier, 32, said. “The project was building a website for a small law firm in Chicago for $500. I was so pumped to sign my own client, but really realized I was onto something when I sold a $50,000 website to a much larger law firm about 60 days later.”

From that point on, Sabatier devoted himself “150%” to building his business, sacrificing much of his free time to do so. “Within a year I had made almost $300,000 and left my job to become a full-time entrepreneur,” he said. He says he went from having $2.26 to his name to over $1 million in assets in five years.

Sabatier recommends that millennials who feel they’re in a professional rut should look for as many extra revenue streams as possible. Keep searching until you hit upon the gig “you like the most that makes you the most money.”

But you may already know which business you want to target. Taso Du Val, the cofounder and CEO of the freelance talent network Toptal—which counts J.P. Morgan and Airbnb among its clients—had a singular vision in mind for his company. He felt secure in his idea when Toptal signed its first deal. “The ability to scale it, for me, was clear,” Du Val, 32, said.

Want it more than anything else

It goes without saying that accruing significant wealth at a young age requires focus, but the sheer amount of dedication can be too much for some to bear.

“You have to really want it. A lot of people say they want, but they don’t really want it,” Sabatier said of the effort required in becoming a millionaire. “You have to cancel your Netflix subscription and stay off Instagram and focus on building a business. You have to be willing to spend your extra time learning and pushing yourself. Read business books, listen to podcasts, or take a free online course instead of watching Netflix. Focus on investing in yourself and your skills. Slowly you’ll start seeing money-making opportunities in places you’ve never seen before.”

That doesn’t mean you should drive yourself mad or lose out on worthwhile experiences. Sabatier went “overboard at times and struggled with finding balance” between work and everything else, and it ultimately led to “regrets,” he said. “I was working 80-to-100-hour weeks for a few years in my mid-to-late 20s, so I missed out on a lot of opportunities to hang out with friends and to travel as much as I wanted to.”

Value your time. It is money…

If you feel yourself stagnating in a nine-to-five routine, it may be time to rethink what those hours mean to you—and their potential earning power. That was a revelation for Sabatier as he embarked on his new career.

“The biggest lesson for me came from the book Your Money or Your Life by Vicki Robin, which in my opinion is the best book on money ever written,” he said. Among the takeaways is that whenever you’re working for a paycheck, you’re trading large pieces of your life for money. “This blew my mind and the mindset shift was immediate. I started valuing my own time and tried to make as much money as possible for my time.” He believes in figuring out the right amount of money you need to support the kind of life you want, and aiming for that, so you can free up time to do everything you’ve dreamed of.

…And make money by adding value

The key to large earnings often lies in understanding what it is you have to contribute and how it’s received by people in the position to pay you. Simply being young and hungry isn’t quite enough.

“Money is a means to add value. You make it by adding value and you spend it on what’s valuable to you,” Du Val said. “I understood its importance by having little of it and studying every intricate component that adds value to a business.” His keen ability to identify how an innovative talent network like Toptal could serve major companies in new ways propelled his business. Toptal supplies freelance software engineers to clients with fluctuating demands.

‘Work to invest, not to spend’

Just because you can make a lot of money doesn’t necessarily mean you’re good at holding onto it. But saving is essential to seeing more commas in your bank statements.

“Common wisdom is that you should save 5-15% of your income depending on who you ask. But if you can push it to 25%, 50%, or higher you can dramatically cut the number of years it takes to retire,” Sabatier said. “Sure, you have to cut back, but you should view saving as an opportunity, not a sacrifice.”

And once you’re able to save money, putting as much of it in a diversified investment portfolio as possible is the fastest route to wealth-building. “I was saving at least 60-80% of my income and put literally every dollar I made on the side into investments so it could grow. I worked to invest, not to spend,” he added.

Embrace the openness of being a millennial, but also be tough

Being a digital-native generation puts millennials at the forefront of the new economy. And as traditional office schedules slowly fade away, they’re primed to take advantage of new modes of working.

“You can make money doing tons of different things online from anywhere in the world. That’s empowering. We are super scrappy and are figuring it out,” Sabatier said of his age cohort.

But Du Val has observed a certain personality quirk among his generational peers that could put them at a disadvantage in becoming self-starters who add value to the world and make a lot of money while doing so.

“They seem to be easily offended,” Du Val said of American millennials. “This is often correlated with being weak, so I would suggest to improve that.”

Part of developing strength, after all, is acknowledging your weaknesses.

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