How to tell my friend she smells?

Ok, I have this best friend. Shes nice, and compliments me a lot. But I absolutely hate sitting next to her! Her breath smells really bad like a mixture of pee and poo. She is musty under her armpits, her teeth are SUPER DUPER yellow and i don't even know if she brushes her teeth everyday. Her hair is always a mess and looks like it needs shampoo and conditioner. As you can see, shes a good friend but i don't like being around people with really bad hygiene. I don't think I'm all that and I'm better than her but my nose cant take it. How to tell her she should fix her hygiene without her getting mad at me?