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.

Before Krista LeRay launched her side hustle, she spent six hours painting a single 4-inch by 4-inch cotton canvas with a fine-tipped paintbrush at her kitchen table.

"I would wake up and paint the entire day until 2 a.m.," says LeRay, 33. "My pinky went numb from holding a fist [around the brush] all day long."

The result: a canvas ready-made for needlepoint, a craft that's essentially paint-by-numbers for embroidery. Needlepoint was LeRay's college hobby, and after picking it back up during the Covid-19 pandemic, she decided to try selling her designs on the side.

LeRay spent $7,000 on supplies, using money she'd earned as a full-time lifestyle blogger, and launched a Shopify website for Penny Linn Designs in September 2020, she says. She was unintentionally early to a trend: As the pandemic raged, needlepoint aficionados searched for online canvas sellers, and LeRay was among the first. She announced Penny Linn's existence on her blog and Instagram account, and her first 500 canvases sold in two hours, she says.

The business has steadily built momentum since then. Penny Linn brought in more than $4.4 million in canvas, thread and accessory sales last year, according to documents reviewed by CNBC Make It. The company was profitable in 2024, with a 36% margin, says LeRay. She has 10 full-time and 24 part-time employees, and a soon-to-open 5,000-square-foot retail location in Rowayton, Connecticut.

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The company's canvases, now made by a variety of designers, range from roughly $30 to over $100 for each "coastal preppy"-inspired pattern — blue and white chinoiserie vases, bowed sun hats and cursive prints of phrases like, "Your email did not find me well."

Initially, LeRay worried that the side hustle wouldn't be worth her time. Despite selling a lot of canvases, it was time- and labor-intensive, whereas she could "post a minute-long Instagram story and make a couple hundred dollars," she says.

"I was making really good money from blogging. It was my retirement plan," she adds.

But fashion and beauty posts felt insensitive to her at the pandemic's peak, and after she had her son in 2022, she felt less comfortable posting her personal life on the internet. She took her side hustle full-time later that year, after it surpassed $416,000 in annual sales.

Here, LeRay discusses whether her business is replicable, how to monetize a hobby and the thick skin you need to run an online business.

CNBC Make It: Do you think your needlepoint side hustle — or any sort of successful crafting business — is replicable?

LeRay: I would say yes to both. I'm definitely a more-is-more type of person. I think there's room for everyone and everything, especially in needlepoint, because there are way fewer physical stores than there used to be.

There are a lot of critiques online recently about monetizing your hobby. You don't have to, of course, but if you're really passionate about it and you have a unique perspective, why not?

Before Penny Linn, you were a successful blogger. What kinds of skills help you monetize your hobbies?

I'm very personable. I know how to connect with our customers online, partially because I am our customer. I know what products to create and how to promote them on social media.

I also have the kind of thick skin you need to run a business. I was picked apart as a blogger, so now I'm able to differentiate between constructive criticism and hurtful criticism.

I give myself 24 hours to be upset. In those 24 hours, I can cry and sulk and eat cookie dough. I can be upset and sad and angry and disgusted and hurt as I want. I talk to my husband, to my mom, to my therapist, to my best friend.

Then, the next morning, after I get a good night's sleep, I say to myself: That's behind us. We gave it the attention it needed. Time to move on.

Crafting trends can ebb and flow. Do you think it's risky to commit yourself to a product that could lose popularity?

Needlepoint's popularity always goes in waves. I think millennials caught on during the pandemic — we were all looking to get off our phones, away from the news cycle and do something peaceful for our minds. The result of that was a ton of new needlepoint designers.

The great thing about needlepoint is once you get somebody involved — someone who is doing it as a hobby, not because it looks cool on TikTok — they find it hard to put down. That's why people stitch into their 90s. You can create gifts for your friends, your spouse, your children and grandchildren.

It's something you can put down and always come back to. Right now, we have a 60% returning customer rate.

Given that embroidery has existed for so long, how do you stand out from your competition?

I remember going to a needlepoint shop before Penny Linn was even a twinkle in my eye. It was heavily marketed to a specific, older generation. When I created my shop, I focused on canvases I would want.

I made some with pop culture themes. I made them younger, fresh and more affordable than when you go into these shops, and they have massive tapestries that cost $1,000 and take forever to make.

I just wanted more accessible projects, like an "Ew, David" sweater, and something to represent my love for New York coffee.

This interview has been edited for length and clarity.

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