Since I've never done this before, anyone have any sort of tips as to how to go about this? Do I ask at check-in or at the gate? When is it best to ask/arrive? Is it rude to ask more than once? Can I (non-elite) get #1 on the list? Are there any strategies to get them to up their offer? When to ask to get rerouted to a new destination?

I'm just so fuzzy about what to do, and afraid to be beat out... anyone have any tips as to a sort of systematic way to ask to be bumped once a ticket is already booked?