As soon as he arrives to his office, just before 8 a.m. each day, Xander Maddox makes his way to the kitchen and lounge area, where large windows drench the space with ample natural lighting.

Usually his colleagues aren’t yet in at that hour, so he makes himself a cup of coffee and positions his phone in front of the window with the camera on and facing him. Then he hits record and steps back to capture the day’s outfit:

A black leather jacket.

A bright blue sweater from COS, Margiela loafers and two cups of Raisin Bran for breakfast.

A white T-shirt, gray pants and cherry red Nike Air Rifts, which he described as “a calm office fit.”

The whole process takes about five minutes. Then he has to upload.

“I try to do the same routine every day just to make it cohesive,” he said in a phone interview.

Mr. Maddox, a 31-year-old executive assistant at a finance company in Jersey City, N.J., isn’t doing this as part of his day job, but for his side hustle as a fashion content creator on TikTok, where hundreds find inspiration in the looks he put together.

Fashion influencing is a billion-dollar business, by some estimates, and many creators aspire to make it their full-time job. But for office-style influencers, their side hustle depends on their main hustle. They’re working at — and showcasing — their style at their real-life offices: law firms, tech companies, call centers, advertising agencies. Several times a week, they discreetly find the perfect spot in their break rooms or restrooms to record their ensembles for the internet.

After all, where else are you supposed to shoot #professionalfashion, #officeootd and #workfashioninspo videos but at an actual office?

In conversations with around half a dozen office-wear influencers in recent days, one thing was clear: You do have to time it right.

And posting your style at the office can backfire. Last week, McLaurine Pinover, the spokeswoman for the U.S. Office of Personnel Management, came under fire after CNN reported on her workplace-style influencer videos, filmed in her office and posted on Instagram as her agency oversaw the layoffs of thousands of federal workers as part of an order by the Trump administration. She deleted her Instagram account, @getdressedwithmc, soon after the news outlet reached out to her.

“There’s a lot of emotions around the government and the state of the world we’re in right now, so I think you got to read the room,” Mr. Maddox said of Ms. Pinover’s case. “If you are in a highly visible job and you’re doing something that seems to be insensitive to the masses, then you’ve got to be able to have that common sense.”

As someone who is 5-foot-10 and broadly built, Mr. Maddox said he had to be meticulous with his shopping, prioritizing pants and shirts that would fit his frame. He would describe his style as “cozy, but elevated” and aims to inspire men, especially those with his body type, who want to express personal style in the office. Many of his colleagues follow him online with enthusiasm and support, he said. They haven’t spoken about it directly, but Mr. Maddox said he was also pretty confident that is boss was OK with it.

“As long as it doesn’t affect work,” he said, adding that his boss has a large social media presence as the chief executive of the company.

Five years after the coronavirus pandemic sent many employees home to log into meetings in loungewear, including new college graduates who began their professional careers on their couches, many are still unsure how to show up for work.

“After Covid, people didn’t know how to dress, because I definitely had no clue,” said Whitney Grett, a 27-year-old I.T. account manager for a staffing company in Houston. “Everyone was wearing sweatshirts the first year.”

Ms. Grett joined her current workplace remotely in early 2021, several months after she graduated from college. She was excited when it was time to return to the office and she could experiment with different ways to dress for work. Last summer, after receiving compliments from her co-workers about her outfits, she decided to start sharing her work looks on TikTok.

“It got to the point where I was like, I guess I’ll just start posting these because it just gave me another hobby to do, honestly,” she said.

In her videos, which are seen by thousands, Ms. Grett poses in front of the glass doors of an unoccupied conference room to capture her look for the day. She and a work friend usually meet up with a tripod around lunchtime to avoid foot traffic. Sometimes they have to wait until the end of the day to shoot if the office is really busy.

“I get some comments from people being like, ‘Oh, I could never do that,’ and I’m like, ‘I understand,’” she said. “I have a very supportive team — I’m not the first one who posted videos from the office before. I think they’re happy that I keep it to a little room.”

According to Jaehee Jung, a professor of fashion and apparel studies at the University of Delaware, office-wear content is popular today because younger audiences, especially ones that started their careers in a hybrid work world, are desperate for guidance on a very basic question: How should I dress for work?

“You’re not at home, so you do have to think about what are some of the rules that could be considered in the working environment,” she said. “Because depending on the profession and industry, you do have some different etiquettes, different tolerance of formality.”

According to Professor Jung, shooting office-wear content in an actual office offers influencers one major advantage: being automatically perceived as an expert. That generic conference room décor proves that someone hired them to work in an office, so they must know something about getting dressed for one.

Vianiris Abreu, a 30-year-old human-resources manager at an advertising agency in Manhattan, said one of the reasons she began posting office wear on TikTok in 2021, when she returned to an office, was that she had missed dressing up for work. Working in a somewhat nontraditional environment allowed her to be more innovative in her dress than many would expect.

“Perhaps what I wear is not something that all H.R. people wear, but it’s definitely normal being that I work in the advertising industry,” she said, adding that she doesn’t divulge too much online about where she works and what she does.

Ms. Abreu said that shooting in the office — she usually spends about 15 minutes a day recording what will become a seven-second clip on TikTok — comes off as more authentic.

“I think for me, the aesthetic of the office is very pretty, and the engagement seems to be higher,” she said. “But I also think it just shows me in the office, which is the whole point of it.”

In many cases, these side gigs can pay off. Last year, Mr. Maddox, the executive assistant in Jersey City, said earned around $2,000 in sponsorships, payments and merchandise from brands. He describes this extra income as “play money.” But he is selective about the work.

“I don’t take every opportunity that comes in because it’s not my full-time job,” he said.