It wouldn’t be a stretch to say that Abbey Brandon is a one-woman start-up.

With her blog, District Dress Up, and related Instagram and Twitter feeds, Brandon is making money as a social-media “influencer,” with brands paying her in fees or free products to wear their clothes and accessories on these platforms. She has had sponsorship deals with the likes of Old Navy, French Connection and Loft.

The stylish photos she and many other influencers post online are designed to look effortless and natural. But make no mistake: Each image is the product of several layers of carefully honed business strategy.

Take, for example, a recent series of sponsored posts that Brandon did for Nordstrom Rack, a brand seeking publicity for the opening of a store in downtown Washington. Brandon said she replied yes within four minutes of receiving the email pitch.

“If I’m not doing it, someone else can,” she explained during a photo shoot two days later.

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Before long, she had a phone call with a brand representative to talk through details. And then she was on an almost four-hour hunt at local Rack stores to put together outfits for the autumn-themed shoot.

This was not as simple as just picking out pieces that fit her personal style: She also was trying to zero in on garments that would be available both online and in stores, an effort to maximize the number of sales she could drive and the return on investment for the brand.

During the photo shoot, there was still more tactical work to be done: showing the garments in a way that would make people want to buy them.

“I think the dark door is not letting the pants pop,” she told the photographer at one point during the session, prompting a move several feet away to a lighter backdrop.

Later in the same shoot, she made sure a Trina Turk coat was photographed from different angles to show off its unique, asymmetrical hem. When getting close-ups of a purse and wallet, she added some colored leaves to the frame to pump up the seasonal vibe.

After the shoot, she spent 30 minutes examining the photos and selecting favorites, and another three hours designing the posts for her blog. All told, Brandon said, she spent about 16 hours creating the Nordstrom Rack content, including elements such as hairstyling and makeup before the shoot, and responding to reader comments.

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Brandon, who has 31,000 Instagram followers, is intensely strategic about all of her fashion posts, even when they’re not sponsored: She never mixes jewelry from different brands in one outfit, because she bets that the brands are less likely to share from their own social accounts a photo that includes competitors’ items. She wants those “shares” from the brands, because they’re likely to boost her own follower count. And a higher follower count can translate into better sponsorship money down the road.

She avoids promoting shoes or handbags in highly seasonal or limited-edition colors, instead opting for styles that will have a long run in stores.

“The more someone sees something, the more they like it,” Brandon said. “It’s kind of like listening to a song; it will take you two or three times to know or be familiar with the song.”

Brandon also has a framework for deciding whether to accept sponsorships in the first place. She thinks of each as being like a “political endorsement,” a testimonial to her readers that this is a brand she trusts. And then she considers not just whether she personally likes the brand’s aesthetic, but she also checks to see how her readers responded to clothes from that chain in the past.

“I try to only work with brands that I know people like that I post [about them] and that will convert well,” Brandon said.