With more than $300 million in annual revenues, Nasty Gal is killing it at e-commerce. Here’s how founder Sophia Amoruso perfected the winning business formula.

“Just be a nice person at work,” Sophia Amoruso writes in her 2014 book #GIRLBOSS, a combination memoir and self-help book that inspired thousands of Millennial women looking to get ahead in life and business.

“If you are a total terror to work with, no one will want to keep you around. And the worst kind of mean is selective mean—the people who are nice to their boss and superiors, but completely rude to their peers and subordinates. If you are a habitual bitch to the front desk girl, the security guard, or even the Starbucks staff downstairs, the news will eventually make its way up the chain. And the top of the chain ain’t gonna like it.”

Amoruso knows a lot about being at the top of the chain. She began her clothing company, Nasty Gal Vintage, as an eBay store, and in the beginning, the clothing store’s main form of advertising was friending hip-looking girls on MySpace (after all, it was 2006). In 2008, after being suspended from eBay for promoting her upcoming stand-alone e-commerce store, Amoruso launched Nasty Gal as an independent website. Then, seemingly overnight, her company had become synonymous with a certain type of young, hip, rebellious style—one that’s equal parts rock club chic and boho hippie festival. It’s a formula that clearly works: by 2012, Nasty Gal’s revenues swelled to a reported $100 million. Amoruso was only 28. Today, Nasty Gal has a lavish downtown Los Angeles headquarters, millions in venture capital funding, and, for Amoruso, a white Porsche that she paid for in cash.

At its simplest, it’s a true rags-to-riches story, and Amoruso’s takeaway message is loud and clear: work hard as hell, be relentlessly positive, treat everyone you see on the way up with kindness and respect, and you’ll work magic.

It didn’t hurt that Amoruso knew how to empower and forge unique connections with her audience either, which she had long defined as someone who wants to be the best-dressed girl around—without spending an arm and a leg.

“I always knew that Nasty Gal was about more than just selling stuff. What we were really doing was helping girls to look and feel awesome before they left the house,” Amoruso writes in #GIRLBOSS.

She refers to a time when she was perusing a vintage store in San Francisco when a girl working there confessed that in order to get outfit inspiration before going out on Fridays, she visited Nasty Gal.

“I started to realize that, though I’d never intended to do so, I was providing my customers with a styling service. Because I was styling every piece of clothing I was selling head to toe, from the hair down to the shoes, I was showing girls how to style and express themselves and how to be confident in their own skin. This realization was one of the most profound and welcome ones I’ve had with the business,” she said. “Nasty Gal became a feeling—one that unified our customers. And that makes us about so much more than just selling clothes.”

That connection extended to Nasty Gals’ social media presence, too, which Amoruso ultimately credits for helping to get her business off the ground in the beginning. Because Nasty Gal’s ideal customers live online (that's you, Millennials), the company took to Facebook, Instagram, Tumblr and Pinterest to create a cult-like following. Amoruso used social media as a channel to build a culture around the brand, convert fans into sales opportunities, promote new products and effectively address customer questions and concerns. It was that constant conversation with customers that created such a loyal following.

“Nasty Gal really emerged from a conversation. I’ve probably spent more time than any other brand reading every last comment. To listen to people the way you’re able to online is very powerful. I think other companies are only now starting to figure it out,” Amoruso said.

But in the end, Nasty Gal’s success all comes back to Amoruso, her drive and her ability to take risks. It's clear she’s doing something right—last year, Nasty Gal surpassed $300 million in revenues. It also topped industry bible Internet Retailer’s list of the year’s 500 top e-commerce performers, beating out the likes of Apple and Amazon. The company’s runaway success has also made Amoruso herself very wealthy. This year, she made her debut on Forbes’ second annual list of America’s Richest Self-Made Women, with an estimated net worth of $280 million. In case you were wondering, that makes her richer than Beyonce. And at 32, she’s just getting started.