when asking a girl out, don't put the pressure of making the decision on her... girls hate to decide and hate men who can't decide, but like to be respected (you decide and then inform her, not decide and just expect her to get along).

instead of saying
"hey, can I go out with you for a movie this Saturday?"
say
"hey I'm going for this movie on Saturday, it'll be great if you can join"

It may sound the same but it's different. The former is 'asking for permission' and the latter is 'extending an invitation'. So ask yourself, is she your potential mom or potential girlfriend?