How to get a girl's number?

Just ask her if you can get her number cause you got a new phone. But really, if you're friends it shouldn't be weird at all, unless you make it weird. No reason for her to jump to conclusions unless you are giving off hints that you like her, which in that case if she doesn't hear to your signs or begins to shuffle away then maybe it wasn't meant to be. Getting into a relationship with a friend if you're not in that 'zone' could really make things difficult between you too if things don't work out.. so weigh out the pro's and con's of your relationship before you try to push it further.