Umm… we wouldn't say that. You never tell a person it's bad unless you're their mum or husband or bratty younger sibling. We would more likely say something along the lines of:

"You look so grown up with your hair like that." Translation: You look like your grandma. (or a church lady).

"Wow. That's some hair." Translation: Is that a rat's nest on top of your head?

"I love a great updo." Translation: Your is NOT a great updo.

Etc., etc., etc.