Crush on a chick.. help?

im 17. I have a crush on this chick. but its a weird thing about me, i tend to talk alot. Im acctually not an introvert at all, i can start a convo like wham bam, but when it comes to talking to girls, my weird sence of humor gets me nowhere... i have the hardest time in the world just talking to a chick i like. im just wondering how any 'normal' person would ask a girl out. like you know, what dyou do. Cz im stupid about girls, really ...whats a girl like (in general) and what do they concider creepy... thanks everyone... (how about choclates? thats romantic right? :P... )