Finding your perfect side hustle might be easier than you think — and it only takes 15 minutes, says Alice Everdeen.

In 2020, Everdeen launched a side hustle as a freelance voiceover artist. She grew it into a full-time business that brings in up to $15,000 per month, according to documents reviewed by CNBC Make It — and when her earnings dipped slightly last year, she decided to search for another source of cash on the side.

She picked up a freelance job facilitating skill-building workshops for a company that hosts career trainings. In those classes, she teaches her simple strategy for figuring out what side gig to start.

"I have people make two separate lists: One is what people's skills are, what they're good at, then another of things they enjoy, their passions and hobbies," says Everdeen, 33. "Then, I have people look at both sides of the list and try to combine them."

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If you love dogs and own a house, you could try dog-sitting, for instance. If you are strong and like to help your friends, you could look into becoming a professional mover. In Everdeen's case, the strategy helped her find those skill-building workshops in the first place, she says.

"I wanted to do more speaking ... but I really enjoy the helping people aspect of presenting and virtual facilitating," says Everdeen. "I looked for facilitating jobs, and found one that was a good in-between."

The strategy worked for her: The new side hustle helped stabilize her income, which is highly valuable for any freelancer, she says.

Tailor your side hustle to your lifestyle

More Americans than ever before have side hustles, to fund a variety of goals — like pursuing entrepreneurship, paying off bills and debt, or saving up to afford big-ticket items like cars, houses and vacations.

Everdeen's strategy can be a good starting point for anyone trying to join the side hustle craze. Kathy Kristof, whose blog SideHusl.com has reviewed more than 500 side gigs, also recommends asking yourself two more questions.

1. How much do I want to work? This can help you decide between more active and passive side hustles.
2. Do I want to run a business alone? Big and small side hustle platforms from Fiverr to Contently can often bring customers to you, taking some marketing and advertising work off your plate — but for a cut of your earnings.

Then, make sure your side hustle solves a problem or falls into a specific niche, Kristof says. Her website offers a quiz that helps visitors narrow down their side hustle options based on interests, skillsets and available time.

"There's too many generalists," says Kristof. "Be specific about what you offer and just take the time, even if it's a month, to hone down your elevator pitch."

Mark Cuban's similar advice

Billionaire investor Mark Cuban has given advice similar to Everdeen: Instead of following what you love, "follow your effort," he said in a 2017 Amazon entrepreneurship video series.

"A lot of people talk about passion, but that's really not what you need to focus on," he said. Instead, "look at where you put in your time, where you put in your effort — that tends to be the things that you are good at. And if you put in enough time, you tend to get really good at it."

Cuban set aside his childhood dream of being a professional basketball player when he "realized I had a 7-inch vertical," he said. Years later, after selling audio streaming company Broadcast.com to Yahoo for $5.7 billion in 1999, Cuban bought a majority stake in the NBA's Dallas Mavericks.

"It was all about fun," Cuban, 65, told NBA player Draymond Green's podcast, "The Draymond Green Show," in April. "That was like a dream ... I didn't even negotiate, I was just like, 'Yes, whatever.'"

Cuban sold his majority stake in the Mavericks last year to the Adelson and Dumont families, who run the Las Vegas Sands casino and resort company, in a deal valued at $3.5 billion. Cuban reportedly retained a 27% minority stake in the team, plus control of basketball operations.

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