Cassiy Johnson always wanted a second income source. But selling concrete candles and coffee mugs swirled in nail polish from her Howell, Michigan, home proved too time-consuming and heavy to ship.

Then, she tried designing T-shirts.

It was April 2020, and Johnson had been furloughed from her full-time job as a daycare salesperson, where she made $70,000 per year. Her Etsy shop launched the next month — and in the fall, it brought in $30,000 in revenue in just two months, she says.

Even better, she adds: She spent less than 30 minutes per day on the side hustle, running it entirely on her phone, she says. The rest of her time went toward her new sales job, making $17 per hour. The following year, she made $90,000 off Etsy and decided to run the online store full-time, she says.

The store has brought in more than $766,400 in lifetime revenue, according to documents reviewed by CNBC Make It. Roughly a third of that is profit, Johnson estimates: She brought in $100,900 in her highest-earning month to date, and was able to pocket $26,100 of that money.

Johnson initially ran her business from her phone. She has since moved it to a bigger screen, she says.

Mary Colleen Photography

The store’s success spawned two additional businesses and enabled her husband to quit his job, she says.

“My husband was having a really stressful time at work, and I knew we could live off $90,000 [per year],” says Johnson, 31. “It was a magical time, to be able to be like, ‘You know what, honey, just quit your job.’”

Here’s how Johnson developed her side hustle, giving herself more free time and turning it into three different income streams.

A ‘print on demand’ side hustle

Johnson’s Etsy shop, which she prefers not to name to prevent potential copycats, was inspired by a YouTube channel. The account was dedicated to teaching viewers about “print-on-demand” stores, where sellers create designs on blank T-shirt templates — called mock-ups — and send orders to manufacturers, who print and ship them.

It seemed “simple and easy,” Johnson says. Her strategy is straightforward, she adds: Figure out what “people are already looking for [and] put something up for sale in front of them.”

Once per month, Johnson does a research deep dive, searching Etsy’s site for trends worth jumping on. She also looks for inspiration while shopping at Walmart and scrolling social media, she says.

She uses graphic design platform Canva to create each new shirt, superimposing the final result onto a pre-purchased photo of a mock-up and uploading it to her Etsy page. The shirt doesn’t actually exist until someone orders it, sending an automated request to a manufacturer and distributor like Printify, which is integrated into Etsy.

Many of her designs involve popular phrases, either in unique fonts or with slightly altered language for demographics like nurses or teachers. Grandmother-themed shirts, for example, feature catchphrases like “My favorite people call me” followed by Nonnie, Mimi, Gammy or more.

Occasionally, Johnson buys an illustration from a designer that “parodies” or “duly references” popular characters or songs — carefully walking a “gray line” to avoid copyright infringement, she says.

She also sells customizable shirts, where people can plug their own text into existing design templates. Her most popular offering in 2021 was a repeatable design featuring letters that were half-cheetah print, half-neon font, she says.

“I made designs that look exactly the same, that say hundreds of different things,” says Johnson.

New streams of income

Two years ago, Johnson realized her business could lend itself to another side gig.

Print-on-demand sellers buy photos of models wearing blank T-shirts, and photoshop their designs on top. Those photos are called mock-ups, and Johnson wanted to sell them to other sellers.

In March 2021, she opened an Esty store called StopMockAndRoll, featuring photos of herself wearing blank shirts for others to buy. It’s a nice side income, but nowhere near as lucrative as print-on-demand, she says.

Last year, Johnson added a third income stream. The YouTubers who taught her how to start her business retired, she says, so she decided to film, edit and star in her own print-on-demand tutorial videos.

She gained 1,000 followers in her first six weeks, largely due to her already-established presence in print-on-demand Facebook groups, she says. Today, her channel has more than 118,000 subscribers.

Johnson declined to share her exact YouTube earnings, but says it has outpaced her Etsy profits over the last six months.

The grit that ‘really sets me apart’

Making those YouTube videos takes up to 20 hours per week, Johnson says. Print-on-demand selling, by comparison, is a lot less time-intensive — but it’s not effortless.

“It’s a grind,” says Johnson. “You have to do the easy stuff every day for weeks and months and years on end, until it works.” Then, you have to constantly stay up-to-date on your trend research, so your products can remain competitive against every other print-on-demand seller, she adds.

Anyone can do it, she says — but to reach her level of success, making money without sacrificing her personal life, you’ll need some grit.

“I think that’s what really sets me apart,” Johnson says. “I’m not afraid to put in the hours, and I don’t have the expectation of like, ‘What if I fail?’ So what if I do? Then I’ll find out.”

CNBC