2 Gen Zers built a skincare business around guilty pleasures and sold $10,000 worth of products in the first month. Here's their advice for starting up now.

• Sabrina Sadeghian and Jade Beguelin are the cofounders of 4AM Skin, a brand aimed at repairing skin.
• They're targeting customers who don't want to give up activities like staying out late.

Name: Sabrina Sadeghian and Jade Beguelin

Age: 23 and 25

Location: New York, New York

Business: A skincare company that aims to repair the damage done to skin through guilty pleasures like drinking alcohol.

Backstory: Sabrina Sadeghian and Jade Beguelin know that people want to do things — like staying up late and smoking — that can end up harming their skin. So they created a skincare company, 4AM Skin, that doesn't shun those activities.

"We're not here to judge anyone's choices," Beguelin told Insider. "We're just here to heal skin from living normal and fun lives."

Last July they launched the business with a $120 product called The Routine. The two serums, which contain vitamin C and superfruits, are designed to hydrate and exfoliate the skin.

The duo started the business as a side hustle, but they hope to make it a full-time endeavor. They said early supporters of the brand included the Vogue editor Chioma Nnadi and Matt James, a former Bachelor.

Growth: 4AM Skin did more than $10,000 in sales its first month, documents seen by Insider show. Since then, revenue has grown by 90% month over month, which Insider also verified with documentation. The two estimated they'd reach six figures in revenue by this summer.

The business has landed partnerships with two tequila brands: Patron, for 4AM's launch party, and, more recently, 818 Tequila, partly owned by the supermodel Kendall Jenner.

On TikTok, the brand's content has more than 1.5 million views. High-profile fans include Kate Barlett, an influencer who has 1.2 million followers on TikTok, and Christian Cowan, the fashion designer known for dressing celebrities like Lil Nas X, Cardi B, and Heidi Klum.

Before 4AM Skin: Sadeghian is still a student at Georgetown University's medical school. Beguelin works for the ad-tech company Ampush, where she helps grow the direct-to-consumer brand clients.

Challenges: They said that time management had been a problem but that they'd learned to prioritize the projects most important to the brand.

Business advice: "Be curious and excited about every single part of the business," Sadeghian said. "If you told Jade or me that we would be plastic and glass experts and enjoy it, I would have laughed. But that's what it took to make the packing we love."

Business mentor: The two said Emilie Heathe, the founder of an eponymous beauty brand, stressed the importance of asking other entrepreneurs for advice on obstacles instead of trying to reinvent the wheel.

Why now is the best time to start a business: Beguelin said the democratization of the internet made it the easiest time to start a business. "Especially with TikTok, it seems easier than ever to go viral by telling a story that people resonate with," she added. "Most of our community has been built through Instagram and TikTok."

On hiring: Right now it's just Sadeghian, Beguelin, and a part-time student intern. The cofounders hope to hire a community manager later this year to help maintain relationships with customers.

On managing burnout: Sadeghian likes to take walks to clear her mind, and Beguelin starts her days with a workout and matcha tea.

"We get caught up in these daily stressors of deadlines, paperwork, emails," Beguelin said. "Finding fun in what we're doing is why we started 4AM, so it's important to keep sight of that."