In this weekly feature, InStyle’s Fashion News Director Eric Wilson shares his favorite fashion moment of the week, and explains how it could shape styles to come.

The Moment: “Hey, you’re in our mustache shot,” joked Liv Tyler to some guy at Stella McCartney’s resort show in a garden on Elizabeth Street on Thursday evening (above), as she held up a cell phone to photograph the models who were dancing, blowing bubbles and posing with candy mustaches on their faces. “Get out of the way!”

The resort shows taking place in New York this week are about more than just commercially savvy clothes that will take retailers through the long winter season. They are just as much about social media moments and brand promotion, as when something adorable happens and everyone takes note on Instagram. I was at Carolina Herrera’s showroom Tuesday evening when I spotted the designer nestled at the center of a group of her models, facing a dozen editors with their phones out. It was like walking in on E.T. hiding in his closet filled with dolls.

At Michael Kors on Thursday, the designer was describing the looks as they came out one by one, including a flirty floral dress that was remarkable for its versatility. Wear it with black tights and shoes in New York or a sun hat and sandals for lunch in Los Angeles, he said, just when an editor’s cell phone started ringing. He joked that it must be a potential customer calling from L.A. who had just seen it on Instagram.

This Week's Wow: Resort Trendlets 2Courtesy Photo (2)

Why It’s a Wow: The good news from resort so far is that the clothes are extra lively this season, with a strong sense of 1970s chic coming from designers like Derek Lam, Gucci’s Frida Giannini, Calvin Klein’s Francisco Costa, and Stella McCartney. At InStyle, our editors are mad for a trendlet we’ve seen of wide-leg pants, especially the super-slouchy sailor pants at Gucci that featured a wicked print of night-blooming flowers, a collaboration with the artist Kris Knight (above, left). McCartney offered a crisp version in buttery yellow and soft pajama pants with a print of superhero masks, and Kors showed his wide pants in pink tie-dye patterns (above, right). Ralph Lauren, amid his finely elegant show of dark navy, gold, and polka dots, offered several smart versions, including a pair of floaty pants in navy silk cady with inset strips of ivory running down the sides—just about the finest take on track pants I’ve seen (above, center).

This Week's Wow: Resort Trendlets 3Courtesy Photo (2)

Another key item appears to be the novelty intarsia sweater. Diane von Furstenberg showed one that included a self-portrait (above, right), reclining seductively on a couch (isn’t she always?), and Burberry’s Christopher Bailey offered a witty take on the British weather with a cloud motif and the words “rain or shine” on a crew-neck pullover (above, left).

Learn More: Stay current on the latest Instagram moments from the resort collections this week and next by following our editors online, and if you need a refresher course on the “resort” season, visit my previous Now You Know post.