Years ago, Lisa Eldridge, a makeup artist in London best known for working with models and celebrities, woke up the morning after a fashion industry party looking, let’s say, less than Picture Day ready.

Instead of sliding back under the covers, she decided to do something she had been considering for some time: She filmed herself applying makeup over her blotches and blemishes, giving pointers along the way, and posted the footage on YouTube, then in its early days as a hub of beauty-focused content.

Her idea, she said, was that the best day to show people makeup tips and tricks was the day you had a tired-looking face.

“I do have splotchy redness, my face does feel really tight and dry and oily at the same time — I’ve got weird skin — and my eyes look tired,” she said, sitting on a pink velvet, lip-shaped sofa in her northwest London office, appearing dewy and splotch-free.

Eldridge started posting tutorials on YouTube regularly, gradually amassing more than 2 million subscribers. She was excited by the new medium — “I could actually show people how to do makeup in a way I’d never been able to before,” she said — but initially she kept her online profile something of a secret.

“I didn’t tell anyone in fashion because I thought they’d look down on me,” she said. “I thought publicists would say: ‘She’s on YouTube now. We’re not going to book her.’ ”

Eldridge doesn’t seem to have lost any assignments — these days she posts on TikTok and Instagram, along with YouTube — and now she has an additional job: cosmetics entrepreneur. In 2019, she founded a makeup brand, Lisa Eldridge Beauty.

“I wanted to do something that was authentic, something that people could trust,” she said. “There are no false claims. There’s no smoke and mirrors.”

Like her tutorials, Eldridge’s line feels upscale but not hypey or glitzy. It began with three shades of lipstick. Today it sells about 300 items, including $26 tinted lip glosses and a $62 eye-shadow palette. Many of the products are highly pigmented and stay on longer than might be expected. Even the matte lipsticks tend not to be drying.

Eldridge is not the only makeup artist selling self-branded products. There’s Charlotte Tilbury, with her hugely successful namesake collection, and Pat McGrath, whose line includes what is reported to be Taylor Swift’s red lipstick of choice. There are lines by Gucci Westman, Patrick Ta, Kevyn Aucoin, Serge Lutens, Mario Dedivanovic (the eponym of Makeup by Mario), among others.

Eldridge’s company, however, feels more homegrown than much of her competition.

“I’ve done it a lot slower than them, and I’ve done it without backing,” she said. “My first launch paid for my second launch; my second launch paid for my third launch.”

Neither did she have “a great load of investment,” she added, “so that within two years you’re in all the Sephoras.” Eldridge owns 95% of her company; during the pandemic, she sold 5% to a friend.

Consumer appetite for the brands of makeup artists remains high. For the first half of this year, lines founded by makeup artists or influencers amounted to nearly 30% of overall high-end beauty sales, according to the market research company Circana.

“What sets these brands apart is the trust factor,” said Delphine Horvath, an associate professor in the cosmetics and fragrance marketing department at the Fashion Institute of Technology in New York. “They carry a sense of authority, especially in this crowded beauty market.”

The consumer, she said, believes that experts who work regularly with high-profile clients understand product performance and can create high-quality formulations.

Recently, Eldridge introduced Rouge Experience Refillable Lipstick, which sells for $59. Each of its eight shades comes in a golden tube that looks like something Elizabeth Taylor might have whipped out in “Butterfield 8.” The packaging isn’t designed just for glamour. The containers and refills are made entirely of aluminum, which makes them easier to recycle than a typical lipstick.

High-end refillable lipsticks are having a moment. Chanel, Prada Beauty, Hermès and Dior all have them. With these, many brands promote reusing instead of recycling as a way to lessen the environmental footprint of their packaging.

Eldridge, 54, has been obsessed with cosmetics since she was a child in Liverpool, England. A gift for her 13th birthday — “Stage Makeup,” a 1971 book by Herman Buchman filled with, yes, tutorials — led her to imagine a career in makeup artistry.

As soon as she was old enough, she moved to London to study and get on-the-job training.

Early on, she sold Lancôme makeup at Harrods but said she was fired for recommending other brands. (She still does that on YouTube, suggesting products by, say, CeraVe, MAC Cosmetics and Clinique alongside her own.) And Eldridge had the last laugh: Since 2015, she has been Lancôme’s global creative director.

As Eldridge’s career as a professional makeup artist has grown, so has her personal archive of cosmetics. She has assembled more than 5,000 vintage items, bought mainly at flea markets and estate sales. A handful of them inspired her new lipstick packaging.

In the process, she has become a historian of sorts. In 2015, she wrote a book, “Face Paint: A History of Makeup” and, in 2021, hosted a three-part BBC documentary “Makeup: A Glamorous History.” Her theory, she said in each episode’s introduction, is that “what someone puts on their face and why says as much about an era as art, architecture or food.”

In the United States, Eldridge’s products are sold only on her website. She hasn’t worked with stores in the U.S. because, she said, “I didn’t have the expertise on my team, to be honest, and that side is not really my forte.”

Still, American orders account for about 40% of her brand’s business. Orders doubled in the first six months of this year compared with the same period in 2023, according to the company, which doesn’t publicly release sales figures.

In New York City, Eldridge is looking for a downtown Manhattan space for a pop-up in the first half of next year.

These days, her YouTube videos sit beside posts from a vast range of influencers and self-proclaimed beauty experts, but that doesn’t bother Eldridge.

“I’m not snobby about that,” she said. “Makeup is entertainment now — that’s what it is.”