Pin, post, tweet it: Vying for Fashion Week's 'it' moment

Fashion goers recording the Marc Jacobs fashion show during MBFW Spring 2014 at Pier 57 in New York.
Adam Jeffery | CNBC

It's fashion's biggest event, but still only a fraction of those interested get to attend Fashion Week—an exclusivity that presents a big opportunity for social media heavyweights.

As live streaming demystifies the shows themselves, social media companies are taking it a step further by launching programs to give users virtual backstage passes behind the scenes at New York's Lincoln Center.

At stake is a highly interactive community—one of brands, bloggers and celebrity designers.

"Fashion's always been our biggest vertical," said Valentine Uhovski, Tumblr's fashion evangelist, adding that it's bigger than even food and music.

About 17 percent of the company's top blogs are currently fashion-related, he said.

"People experience Fashion Week in different ways now," Uhovski said. "Before you might look at photos on or read the reviews on, but now the coverage is basically very instant, and Tumblr's one of the platforms that gives you visual gratification right away."

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This season, the company's partnered with Sony Electronics to launch a mentorship program between top designers, such as Oscar de la Renta, Marc Jacobs and Donna Karan, and 20 bloggers. As part of the deal, the bloggers snap photos to upload on Tumblr, which are being featured in an exhibition at Milk Studios in New York.

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Competitor Twitter also has beefed up its presence for this season's presentations. During last season's shows in February, the company saw more than 2 million Tweets about the event.

"Obviously not everyone can be present at Fashion Week, and people can turn to Twitter to catch what's going on," said Jenna Mannos, the company's head of fashion partnerships. "It's consumers' backstage pass to Lincoln Center."

Using the hastags #FashionInMotion and #BehindtheFashion, some designers will be live vining backstage scenes and experiences from the front row. These posts are especially useful for cutting down on fans' FOMO, or fear of missing out, the company said.

This fall marks the first official Fashion Week-related program for Pinterest. Its new Fashion Week hub caters to strong interest on the siteto the tune of more than 2 million fashion-related pins each day. For its inaugural run, Pinterest teamed up with more than 100 designers, publications, brands and bloggers to create boards with suggestions on how to bring runway looks to life and behind-the-scenes images.

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This season, Instagram has set up large display screens in the Lincoln Center lobby and at Milk Studios displaying various posts about Fashion Week. Inside a Lincoln Center VIP area, it also has set up a dedicated spot to take Instagrams and also has another installation at Barneys.

In addition to distributing pairs of Google Glass to select fashion editors, Google is also uploading videos of runway look how-tos and style playlists on YouTube.

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Through Google hangouts, influencers will also get to share their favorite items from Fashion Week, giving consumers a chance to buy them.

The platforms have also increased the interaction between fans and designers, said womenswear and swimwear designer Mara Hoffman. "It makes things more intimate, and I think you can bring your fans and your audience into your life in a way you couldn't before," she said. "The people who buy my clothes know my son, they know my house."

Changing the marketing game

Facebook-owned Instagram landed a big fashion exclusive earlier this year when Oscar de la Renta launched its fall ad campaign on the app—a sign of how important mobile apps have grown to the fashion world.

Womenswear designer Jill Stuart also debuted her fall ad campaign on Instagram, she said. Before her presentation on Saturday, her team uploaded shots of the hair-and-makeup area and fittings.

"It's very important. It's because it's what everybody is looking at, what everybody is watching," she said about having an active social presence during Fashion Week.

For brands with smaller budgets, this additional tool helps stretch marketing dollars.

"We're still a small guy so we don't have the big bucks for ad campaigns and that type of thing so social media is this awesome tool—it's like taking guerrilla to the next level," Hoffman said.

—By CNBC's Katie Little. Follow her on Twitter @KatieLittle.