Be awesome
No offense, but what the hell is this topic? A Cosmo article?
"101 Ways to get phone numbers!"
Really?
"What's your number?" or "Give me your number." Avoid sounding like a sniveling pu$$y, or a date-rapist. You know what these people sounds like. It's literally impossible to f*ck up if all you're worried about is asking for a number.
There, question answered. No need to analyze. And really, if the girl you're asking decides to think hard and deep about the wording of your request before she obliges/declines, then 1) she doesn't want to really get back in touch regardless of what she says, and 2) you don't WANT her number, trust me.
Agreeing with the last two posts here, because I love group think. Sarcasm aside, one's game is the real issue here.
The real issue is that there is only one way to get a number:
Be awesome.
Very simple - that's why it's so difficult. When things are simple, there are no excuses.
Anyway, if you want practical advice, get to know the guy in the room who's funnier, more magnetic, and more adventurous than everyone else in the room. You know, the guy you're jealous of because you're fully aware that he's getting laid a lot. Don't torpedo these people - befriend them.
Ask him what he does, and how he got there. Do you do those things? Not yet, but if you do, you'll eventually be more awesome. And you'll get a lot more than numbers. But, once again, try not to sound like a sniveling pu$$y/date-rapist when asking for advice. DJ forums will sort you out.
Protip: Asking for a girl's number is NOT what will get her interested in you.
Don't even get me started on the kind of guy who asks a girl "Will you be my girlfriend?"
Happy hunting, all.