Isn't the key to just drink as much water as possible before passing out? I've always just prepared a huge bottle of water next to my bed so that I would hopefully chug it before I go to sleep.
Works for me. Except I drink water while I'm drinking beer. Something like 1 drink of water to 3 or 4 drinks of beer. But I'm also at home, on the computer drinking and not out partying. So I don't know how well it translates to being outside the house.
Gotta be careful with amounts here -- one time I drunkenly drank tons and tons of water to the point I actually dehydrated myself even further than the alcohol would've. Worst hangover of my life.
Probably you drank way too much "pure" water, and you upset your salt balance. Most likely if you had had some salts in the water you would have been better off (if not fine).
Kingsley Amis, the novelist, has some excellent essays on drinking. He claimed that if you mostly drank large quantities of neat spirits, a large proportion would end up passing undigested out the other end, but by drinking water you were diluting it to the perfect concentration for max alcohol absorption.