How should i approach a girl for her number?

Hey, I know this girl and she knows me. We're good friends and I want to ask for her number. Any tips on how I should approach?

Well, this is what i think you should do...
while you all are having a conversation or something, bring up the phone number thingy and exchange numbers. Usually it's better if both of you exchange numbers because then your friend will not feel as if you were hitting on her straight out. I don't know if you like her as more than a friend, but just make sure you get to know her before you do anything. Ask for her number as a friend not as a guy that is crushing on her.

try to talk to her and tell her that u wanna talk to her on the phone and exchange nuber and mayby she will say yes