There's lots of ways. The way my boyfriend asked me out was I was talking about someone asking someone else out and he said "Well what would you say if I asked you out?" and I said "Um, well I'd say yeah, probably." and he says "Well, would you want to?" and of course I said sure. Seems kind of boring, but seems to be the easiest way to me.
dont ask her out like "will you go out w/ me" that is BAD. makes you sound like a loser whose never done it before. even if you havent, you dont want to seem like it. say "do you want to get together sometime?" if she says yes, then set it up. and if you know she likes you, well, the you have nothing to be worries about. i dont know what website you went to but i dont think you should go to it ever again.
If you can find out about a movie she wants to watch (or just a movie everyone is talking about & you want to go see) or a cafe (or ice cream bar or something), park, zoo etc. she likes to go to then just ask her whether she wants to go see the movie or go for a drink/ice cream etc. with you, you don't have to ask right out "will you go out with me", just ask her if she fancies going to that place with you. I fyou know she likes you, you can't go far wrong!
25, female, AS with attentional dysfunction