Originally posted by KewpieOr challenge random people from the bottom end of the Player Tables.
Put a couple of games on the Open Invites page and put "beginner" in the game name box.
If you want to improve, though, challenge people a little higher rated than you. Not too much higher, or you won't be able to learn much from their play, but certainly not too much lower, or there won't be much for you to learn.
Richard