|Purging the universe of Xenos scum!|
There are suddenly a dozen people in my local club playing Tau, so I don't think I'll have any trouble getting in plenty of games against them. I expect Tau, Necrons, and CSMs to be a large chunk of the armies at NOVA, so I'm going to concentrate on getting extra games in with them. Then I'll probably browse through some of the codexes to get acquainted with the armies a little further.
I usually play against the same 2-3 armies, so making a concentrated effort to familiarize myself with other ones is important. Nothing makes a game harder than not really knowing what you're up against. That's gotten me into a few bad situations before.
When you go to a big tournament, aside from painting the army, what do you do to prepare?