I assume you mean "your girl friend". You don't..
Talk to her more, become her friend and see what happens from there
build up cofidence onnly ask her if your ready try to talk to her as a friend first then go in for the move
Always remember, a girl is just as shy and worried as you are, so talk to them first. Get to know them, and be their friend, then move up a notch every few weeks. The girl would like a boy to come up and talk to them better.
Talk to him. Maybe you can work something out.
Talk to him about it. Talk to the girl about it.
talk about it to her
HELL NO HELL NO
When you talk to her and she ignores you.
Well sure, it is natural to like any girl. However, I strongly suggest you talk to your friend about how he feels before making any kind of move on her. It could be a good way to lose a friend if you don't. heck yes
talk to them both.
Talk to the girl. She will decide who she wants to date. However be prepared for your friend to hate you.
To make a girl who was once your friend talk to you again, simply remind her of the good times you shared, and how you want a repeat of the same.