has some advice for women attracted to bad boys: "Stop!"
The 27-year-old may play a Shameless
character who's attracted to heartbreakers, but they're definitely not Rossum's type in real life.
"I'm kinda more attracted to the nerd," she told PEOPLE at Real Simple
's Beauty & Balance Botanical Cocktail party Saturday in New York City.
"I'm really into guys who are super smart and funny and can teach me something I don't know about."
Rossum – who's dated her Shameless
costar Tyler Jacob Moore
and Counting Crows singer Adam Duritz
, and divorced
music exec Justin Siegel in 2009 – says it's important to see beyond a guy's looks.
"Girls, and guys too, are so shallow that we don't give a chance to the good guy who's maybe not as cute," she says. "They're kinda like a fixer-upper apartment."
"You need to pick the guy who's really good inside and then give him a makeover," she advises. "Turn him into the perfect version of himself. You can never change what's inside, that's the problem. You can change their jacket and their hairstyle, and buy them a Clarisonic."