[Sterling]

Just tell her you are doing something and was wondering if she might be interested in coming along. That way you aren't typically asking her out, so if she says no, it's not really like you are getting rejected, and if she says yes you get to spend some time actually talking to her. If she does say no, maybe you can find out what kind of stuff she IS interested in and find something like that to ask about later. Either way... don't make a big deal about it.