Christian Siriano: Designing for Taylor Swift Is Good for Business

In the four years since taking top honors on season 4 of Project Runway, Christian Siriano has kept himself busy, building a veritable fashion empire.

His latest venture, an expanded collection for Payless ShoeSource, is an unexpected one for a designer best known for frothy and “fierce” creations, but Siriano is also a shrewd salesman.

“The new expanded collection, when we think about it, is for every customer that walks in the store,” he told PEOPLE at a Christian Siriano for Payless in-store event. “You’re like, ‘Okay, what is the mom wearing to work? What does the daughter want to buy?’”

And with recent coups including dressing Sarah Hyland and Runway mentor Heidi Klum for the 2011 Emmy Awards, Siriano’s business savvy also applies to cultivating celebrity relationships. Working with Modern Family star Hyland “made sense for me because Sarah is such a young, new, beautiful actress,” he explained. “I think she really needed a moment.” And designing for Klum is always a no-brainer. “I would do anything for her. She can call me tomorrow and I’d make something.”

However, it was tweaking a style for Taylor Swift’s Wonderstruck perfume ads that proved to be the most lucrative. “I have orders all day long on that dress,” he says of the blushy, tulle confection, she wears in the shot. “We can’t make them fast enough.”