First of all, asking another guy how to ask a girl out is not lame. And I quote: "He who asks a question is a fool for five minutes while he who doesn't is a fool forever." So if you want to be a wise ladies' man, read on!
Get Rid of Cheesy Pick-Up Lines.
Cheesy pick-up lines might have worked for some guys during the 90's, but those same lines won't work for girls today. And don't even begin citing movies where the guy gets to make a girl laugh by dropping one of those lines. In reality, girls are more likely to laugh in your face or be turned off by such corniness.
Replace "Dating" with "Hanging Out."
If you're already friends with the girl you want to go out with, bringing up the question can get pretty awkward. Even if there's already something between the two of you, it's not always easy to be the first one to say there is.
One way on how to ask a girl out is by asking her to hang out with you instead. "Wanna hang out at Starbucks later?" can give you more results than actually mentioning the word date.
You're not trying to deceive anyone. Essentially, you ARE asking her to spend some time with you. Besides, this allows you to be more comfortable with each other while exploring your boundaries at the same time.
Let Her Know The Itinerary.
Please don't take this too literally and give her a schedule of what you two will be doing should she say yes to you. Asking the question, "Would you like to go out with me?" is too vague and does not really work for the modern woman. What you'll want to ask is, "Would you like to go get ice cream sometime?"
This way, she can give your invitation a little more thought. This also allows her to imagine how the scenario would turn out. Getting ice cream is relatively safe and she should be more than happy to say yes. Unless of course, she doesn't like ice cream in the first place!
Learning how to ask a girl out is a game of trial and error. The rules change over time; and as always, there are exceptions. However, the tips mentioned above comply with today's sassy and sophisticated women. By employing all of them, you can avoid rejection.