Stay loose during backups. If it's a good course, there'll be one or two super tough hole that everyone gets in trouble on, and there will be 3 or 4 groups backed up there all sitting around and complaining about it. And when they finally get on the tee with stiff arms and a head full of watching bad shots, well, things seem to go worse for everyone. Its super important to stretch and stay warmed up and try to take the tee with a fresh outlook on the shot.
I seem to get pretty lucky avoiding the worst backups. I've finished my first round, gone to lunch and gotten back before the last card was in. o.O