Hello.
I have a firend of mine who doesn't liek herself, he just know to say that she is ugly, and many bad things about herself.
I just don't think like her, i'm always saying that she is pretty and she should love herself a more.

I really want to help her, because she is sad ans insecure because of her body etc.

But i don't know what else i can do.

Please, i need advice.

Loads of people have feels abit bad about themselves, it's normal.
If she herself is not happy with her body, remind her that girls keeps growing till about 20-22 (I can't remember exactly), I'm guessing you two are young so that should help a little bit, give her honest compliments, point out what that is good within her personality (Caring, nice etc)

You can also tell her that every guy/girl has their own taste, she'll be or is wonderful to some people who can "see" her.

I don't think you can do that much more, we choose ourselves who we want to be, she herself has to realize that she is better than she thinks she is, as long she doesn't truly suffer from it though, it shoudn't be a problem.
Oh I almost forgot, About 1% of the models are natural or it might be even less, so if she compares herself to them, it might be good to point that out.
I hope this helps you and her, even if it might be just a little.

Thank you for the advice. I'll try it. i really want to help her.

Thanks :)