I ran into my first game with the following;
Rifle (can be rented of course.)
BBs (Use HQ BBs especially if borrowing a gun)
Mask (Protection for eyes ears and face)
Boots. (Already almost rolled my ankle at least 3-4 times in my first two games)
In my white plaid coat, I just claimed to be from the "Southern US Resistance" as a joke. Camo helps, but isn't manditory. I walked into my second match, and when we were coming out people said my camo didn't work because "We could just see that blue mask staring at us through the brush."
Of course I'm claiming psychological warfare on that one.