What to do at a Sadie Hawkins dance?

So my character recently asked a guy to go to a Sadie Hawkins dance, he said yes. Only problem is I've never actually been to one... or any other dance for that matter. Would someone please describe the way it goes? Can they meet there? Does the girl offer to pick him up? What if she can't drive? Do they have to go out to dinner first? What should she wear? Thanks so much!