Proactive Partying Tips?

I'm one step ahead of the game today. I can't handle the hangovers anymore, but I have a Christmas party tonight, so I need your support in the form of tips, tricks and old wives tales, that will help prevent the dreaded hangover.

A pint of water between pints of beer is already on the cards.

Also, please don't tell me not to drink. If I had that kind of self discipline, I wouldn't be here in the first place. Thanks!