When Michael Kors gives style advice, he might just throw in a little relationship advice, too.

Fashion writer Kate Betts asked the designer how he would counsel girls who are trying to keep up with perennially changing trends, and he said she should "take the same approach she takes to guys."

"There's great fling material, and then there's great husband material!" Kors said. "Apply that to your wardrobe and it means invest in the key pieces you'll want to spend time with season after season, the pieces that will help define your style. Don't invest major money in the trendy pieces that will feel old by this time next year. Like dating that guy just for fun — it's not to say you shouldn't do it, just don't sink a lot into it!"