It’s very hard to give advice because, unless you know the person very well, and you know very well what she needs right then, you are going to misfire. I don’t mean that you are going to give bad advice, I mean that you are going to give advice when advice is not what’s wanted or needed. You are always better off listening quietly, if you can, and if something helpful comes to mind and you can’t help yourself, suggest it in as few words as you can manage and very tentatively.
What this is, it’s an exercise in strength: the strength of listening without giving advice unless advice is specifically requested.
If you feel you need to say something — and saying something is a good idea — ask questions. Questions let the person know that she is important, that you are interested in her, that you want to know, that you are trying to understand. This will allow her to understand, too. But if she says, I don’t want to talk about it, well then you have your cue.
Give advice only when it’s explicitly requested and even then, make sure the person actually wants it, instead of just needing to be confirmed in a course of action she has devised for herself. People know best what is good for them. Be a good listener and support people who open up to you.