Quick female interjection here-
Girls are not as difficult as you think...we understand that asking a girl out is really tough and stressful for a guy, and if she's really not interested, she'll totally commend you for having the balls to try, and she might even accept for that reason. Unless she's a heartless bitch, she's not going to completely shut you down.
One of the most important things is to just not be awkward about it...confidence is sexy!! If a guy phoned me and was like hi, I'd like to ask you out on a date...I'd be thinking uh.... ok? Just approach it super mellow- be like, I think it would sweet if you and I checked out a movie this weekend...put her at ease!! And girls aren't retarded- you don't even have to mention the word date...if you ask her to hang out, one on one, she'd be dumb if she didn't realize it was a date type situation.
Point is guys...what's the worst that's gonna happen if you ask a girl out? She says no. Big fucking deal. Yeah, it doesn't feel good when it happens, but at least you tried! And who wants to be with someone who doesn't like them back? So just be confident and treat her well...this shit ain't rocket science haha most girls are dumb enough to fall under the spell of any guy who is nice and in control!
Humor always helps too!! Totally breaks the ice.
Anyways, sorry if I interrupted this little guy session lol, just thought I'd throw in my two cents. Good luck asking her out dude
**And if she says no, play it totally cool. Just be like okay cool, well have a good weekend. Girls will expect for the guy to become totally upset and it'll make them feel better about themselves because that would mean that they are breaking a heart which in a girl's mind means they're hot shit- don't let that happen...don't let her see how upset you are...it'll leave her wondering...and she may just change her mind, because every girl wants to be wanted. Solid fact.