So I know in most cases my best bet is to give her a specific time/place/activity from the gun, because it could spare me the communication game later on and also shows if she's really interested.

My question concerns some specific situation though. I see her once per week during a dance class and there's not too much space for talking (that's the reason I would like to meet her outside the classes). Besides waiting for her after the classes, which I find stalkerish at 11:30pm, the only possibility to ask her out is to have some chit-chat between particular dances/songs.

And that's when I'm going tell her sth along the lines "you know Jane, i may not be the best dancer out there, but... it doesn't mean I wouldn't love to go out with you for a coffee sometine. If you're up to it, just give me your number and I'll get back to you to find some spot". I mean, there's really not so much time for an extended discussion, that's why I thought about leaving the time/place part for text/call. (Btw, I'm indeed a really bad dancer, cause I'm new and hardly learning anything and she very much knows it - thats why this beginning of convo)

What do you think?

Edit: many of you suggest I talk to her much more before that plunge. I don't plan to attend this class much longer, because of my schedule. So I just want to shoot my shot im a best possible way, that's all. I also mentioned theres close to zero time for talking at the classes.