How can I tell my friend she looks like a skank?

I know exactly how you feel! I had a really close friend, and she kinda turned into a...whore. she lost a lot of friends too because their moms didnt want their.kids hanging out with her because she was a bad influence. I just slowly stopped hanging out with her because there was no way i could tell her without her flipping out, getting mad and taking it the wrong way :(