Heeeelp me!
Just remember not to get too nervous during the game: You don't want to be mugged when you are huddled behind your bunker, whimpering and calling for mum.
And, as said before, it's important to have fun. If someone makes a mistake, hey, it's your first time. I hate to have to use them as an example, but Nexus, made up of some great players, had a nightmare. So don't sweat it.
The post about shaking hands before and after a match is so spot on. It's the difference between a team of nice blokes and a bunch of muppets, so just be sporting. Then when your cocker starts spitting air all over the place, one of the chaps who shook your hand will be more likely to help you.
Good luck.