Cool. Thanks y'all for the tips. I looked up the events calendar for the game con and it looks like they're playing Mage and World of Darkness LARP. I've already started reading up on them at the World of Darkness site and am getting psyched to play. I just hope I don't screw up, embarrass myself or get myself thrown out of the game. Perhaps I should announce I'm a noobie first before I sit down...
If you screw up in character, you screw up in character. Do what your character would reasonably do.
If you screw up out of character, apologise, and then try to correct your mistake. Mistakes happen: Do not worry unduly.
It might be a good idea to tell the ST's that you are new to LARPing; any good ST will take a few minutes beforehand to answer any questions that you may have, and probably give you a couple of pointers if you ask them. Find someone else in a larger LARP to stick with to learn the ropes - often, in-game friendships turn into out-of-game friendships.
You mentioned that you will be playing in a WoD LARP (old-school or new-school?) - keep your rulebook with you. Use stickynotes or stickytabs to mark the pages that have often-used rules in them, like how to throw challenges and abilities relevant to your character.
Bring a small stack of index cards for items with you to the game. They are handy, and often required of players. Usually, someone will be short a couple, so extras are nice.
The Doctor (Camarilla chapter: PA003)
a.k.a., Reserved Operand Fault, Cyberpunk bani Virtual Adepts
a.k.a, Rick Vankin bani Cult of Ecstasy