Dutch

Wear some decent socks, makes a difference. most importantly have fun

Don't be afraid to get dirty.. far too many people get hit out because they don't want thier belt buckle to hit the dirt. Also try and keep track of where enemies are even when they're in cover; Short term memory loss always seem to be an issue with airsofters and also be patient.. charging up the middle may work sometimes but you're more likely to have success if no one sees you coming

Oh yeah make sure you have some decent footwear, preferably boots with decent ankle support. If there's anything you forget then one of us who's there will have spares.