This story is part of CNBC Make It's Six-Figure Side Hustle series, where people with lucrative side hustles break down the routines and habits they've used to make money on top of their full-time jobs. Got a story to tell? Let us know! Email us at AskMakeIt@cnbc.com.

One of the first quilts Mike O'Dell ever made was for his sons.

He drew a Star Wars stormtrooper on a 5-by-6.5-foot sheet of graph paper on his kitchen floor, cut the pattern into smaller sections and sewed fabric onto the paper. Then, he stitched the pieces together on a sewing machine and discarded the paper remnants, he says.

He started the process in 2018 and finished the quilt 18 months later, says O'Dell, 50, an Oklahoma City-based nurse anesthetist.

But the actual sewing work — quilting on top of the design, a practice called "foundation paper piecing" — was surprisingly straightforward for a beginner, O'Dell says. He figured that if he hired people to streamline the process, he could make and sell quilting kits with licensed images of nature scenes, animals and characters.

He launched his side hustle, called Legit Kits, in 2020. The company brought in more than $1.25 million in sales through Shopify last year, according to documents reviewed by CNBC Make It, and an additional $150,000 selling quilt kits at Joann Fabrics and Crafts, O'Dell estimates. (On Feb. 23, Joann announced closures of all of its roughly 800 stores, citing bankruptcy liquidation.)

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O'Dell works at Legit Kits one day per week as its CEO and creative director, and spends four days per week at a hospital. Legit Kits' seven full-time employees and four freelance designers keep the business running during O'Dell's nursing hours.

He spends his one Legit Kits day per week largely promoting the company, he says — on social media, particularly Facebook — and networking in professional crafting groups, which helped him land a spot on an episode of ABC's "Shark Tank" that aired in January.

Legit Kits broke even last year, after accounting for costs of inventory, payroll, hiring and a $4,500 monthly rent for a 4,500-square-foot manufacturing space, O'Dell says. He plans to pay himself $50,000 from Legit Kits this year, on top of his $240,000 nurse anesthetist salary.

Here, O'Dell discusses starting a side hustle without prior experience, how he balances his full-time job with Legit Kits and what he wishes he'd known before jumping into entrepreneurship.

CNBC Make It: Do you think your side hustle is replicable? Can anyone successfully create a crafting business?

O'Dell: Sure. There are so many opportunities out there. I took something that's generally crafty and I added [artful designs] to it. They seem similar, because they both take skill, but art is what causes an emotional reaction in the observer.

I wasn't a quilter before I started writing patterns, but my wife was. When she started, I watched her make nine-patch quilts and sew the pieces of fabric together in a grid, like tic-tac-toe.

It reminded me of my first job, when I was still in high school, with a computer company. I did their instruction manual, and drew pictures the same way — pixel by pixel in a computer program.

That's how I drew the storm trooper. It was 1,260 pixels, and it was easy enough for a beginner like me to do. My ignorance was actually a benefit, because when you're an expert at something, you tend to make assumptions. When people don't know stuff, they have to ask a lot of questions. 

How do you balance your full-time job with your side hustle?

I've lost sleep. I've had a lot of stress. But I don't know that there's any sort of burnout that can match medical burnout, and I've had that for a long time.

The burnout that I feel at the hospital fuels my energy to do the other thing for myself. Legit Kits is my brain child. I own 100% of it, and I get to control what happens.

It turns the volume down when everybody's mad at work. I hear it, but I'm just like, "I'm not going to manage my people that way." [Plus] it's kind of hard to beat an anesthesia salary. I've got three kids, and I want my kids to go to college.

I once read in a book on entrepreneurship that [said] when you start a business, you should expect it to take over your life for the next five to 10 years. I started quilting seven years ago, so I'm coming up for air right on time.

I can clock out at Legit Kits without checking my email or texts all evening. I just go and plug my phone in when I get home, and leave it alone until the next day. I'm finally detaching in a healthy way.

What do you wish you'd known before starting Legit Kits? 

Back in the day, when I was watching "Shark Tank," if somebody said they had sold a million bucks' worth of something, I was like, "Yeah! They're rich. They're millionaires."

Sadly, you don't really get to keep most of the money that your business makes. It goes right back into it. When we were consistently breaking $100,000 a month in sales, I was like, "Yeah, this is it." But then you're spending $100,000 a month, too.

What's your plan for growing Legit Kits past breakeven and into profitability?

You have to write your goals down, so there's a 5-foot sign in my office. It says, "World Quilt Domination."

[I'm investing more in] marketing, hiring someone to do custom work for us. The plan is to start with a $10,000 per month budget, and roll profits from the previous month's marketing returns into each month's budget.

Preliminary results: We spent $900 on Facebook and directly sold $6,300 in the first week. I've learned that it typically takes three months before you see the full effects of a marketing campaign, so I'm hoping to have profitability in that timeframe.

I want to start getting on [retail] shelves with some smaller projects that still look cool, and spread out to the masses more. I want to be in all of the boutique quilt shops out there, all the little mom-and-pop shops. I'm just now starting to get recognized by some bigger businesses.

For most quilters, designing 20 patterns is a ton. That's like a life's work. My goal is to get to 100 patterns. I feel like there's still room to push this medium, and I think there's a whole lot of places Legit Kits can go.

This interview has been edited for length and clarity.

Disclosure: CNBC owns the exclusive off-network cable rights to "Shark Tank."

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