Known for its ultra-feminine, romantic designs, dreamy florals, bows, and vintage-inspired pieces, LoveShackFancy has become a go-to for anyone looking to add a little whimsy to their wardrobes.

At New York Fashion Week, E! interviewed LoveShackFancy founder and creative director Rebecca Hessel Cohen at her show, where she shared the story behind the brand’s beginnings, and the three pieces she says everyone needs for fall.

Before the brand became a fashion-world favorite, Hessel Cohen was an editor at Cosmopolitan who couldn't find a dress she wanted. So she made one herself—and, eventually, an entire brand followed.

“Yes. Bridesmaids dress. I was an editor for about eight and a half years, and I couldn't find a dress I wanted. So I made my bridesmaids dresses, and that's what happened!"

“Then I made this gorgeous halter dress," she continued "A lot of side boob. Everyone loved it. And then I made samples, sold them to friends, and then just started making them. That became the story of the beginning of LoveShackFancy.”

Making clothing she actually wants to wear is still at the center of LoveShackFancy's latest collection, which debuted during New York Fashion Week.

Inspired in part by Hessel Cohen's memories of growing up in New York in the '90s and 2000s, the collection also looks to the next generation: her daughter.

“My 13-year-old daughter is like, obsessed with this whole era,” she shared with E!. "We go vintage shopping all the time together. So a lot of the pieces I saw her picking up at vintage shows I was like, you love this again? And she does. And so that inspired a lot of it.”

She even went back into the LoveShackFancy archives to find something really special. “We have a version of my prom dress from the year 2000!" she said.

But if you're less interested in the nostalgia and more interested in what to actually buy this fall, the founder has some very specific advice.

Here are the three pieces she says to have in your wardrobe, and exactly how she would style them.

“Okay, so the number one piece that you need for fall.... It's very simple, but it's our cashmere cardigans, which you can't live without," she told E!.

The Avignon Cardigan features a cashmere-wool blend with intricate knit techniques. This cropped sweater, at once cozy and cute, has a v-neck that descends to three buttons at center front. Pleated blouson sleeves extend to ribbed cuffs at opening. Choose from two colors.

The Cameryn Cardigan is the perfect layer, finished with a sweet bow patch on the back that adds a whisper of whimsy to an otherwise understated silhouette. Choose from two colors.

The Applene Cardigan is designed from a lightweight, luxe cashmere and extra soft. Ribbed trims with loops arrive at the transfer line with buttons down center front. This knit has patch pockets and a boyfriend-like fit.

For Hessel Cohen, the easiest way to make that cozy cardigan feel more fashion-forward is to pair it with one of LoveShackFancy's mini skirts.

“I love [a cardigan] with any one of our cool little mini skirts, because that's a great way to just mix and match everything.”

The Sabrine Skirt is a dreamy slip silhouette adorned with delicate lace trim and a sweet lace bow, perfect for your most enchanting evenings out.

The Rora Skirt is a dreamy tiered mini with a playful scallop hem that moves beautifully with every step. Soft knit construction and a loose silhouette make it as comfortable as it is charming.

Flirty, feminine, and endlessly charming, the Glindy Skirt is a dreamy mini designed for warm-weather styling. This fitted A-line silhouette is crafted from stretch knit fabric with signature laser-cut eyelet finishing at a scalloped hem.

“So you can do a cardigan with the little mini skirt and the oversize-cool jacket so it gives you like a downtown edgy vibe. I love that," Hessel Cohen said.

The Eveline Jacket is an oversized bomber crafted from genuine leather, finished with a plush collar for a cozy, elevated contrast. A ribbed hem keeps the relaxed silhouette grounded.

This chic, camel-colored suede jacket boasts a fringe layer designed from a soft, luxe lamb suede. The dramatic leather fringe details line the entire sleeves, the front and, the back, giving this piece gorgeous swaying movement throughout. This is the statement jacket you have to have.

15 Fall Jacket & Coat Trends to Shop Now, From Barn Coats to Faux Fur

The E! Insider Shop editors and writers search the internet to find the best products out there. We interview expert sources, comb through customer reviews, and use our own personal experiences to make shopping easier for our readers.

As an editorial team, we independently create content and determine coverage based on research, reporting and what we think our readers would like to read about. The goal of our content is to provide a service and inform readers who are on the hunt for the latest products to help make their life better. Items are sold by retailer, not E!. Pricing and availability are accurate as of publish time.