No experience doing it at Maryland, but this is probably a good place to start. Here's a better map (PDF). Also, you can purchase ahead of time here.
Here's some very quick insight from one of their fans last year. Guessing you can't do lots 1 and 9 because they're scholarship donation lots but someplace nearby would probably work.
Anyone know how far the Metro station is from the Stadium? Will be visiting our son in Arlington and heading up to the game Saturday and still figuring out the best way to get there.