Bartender checking in.
not many of these things will work. I'll share what I know to be true through research and alcohol classes I have attended.
Drinking water throughout the night is double sided. Meaning, you're not going to drink as much alcohol if you're drinking water because you are less thirsty, therefor not wanting to drink at all. booooo
Eating something fatty before drinking will slow the absorption rate of alcohol. This only affects the rate at which you get drunk though, nothing to do with hangovers.
caffeine is so stupid to mix with alcohol, ESPECIALLY energy drinks. I dont even know why it's legal still to be honest. People assume the main reason is because you're mixing a stimulant with a depressant, but there's a lot more to it. The caffeine and sugar take effect first. meaning you feel fine and dandy after 3 jagerbombs, actually you can concentrate better than before taking the shots. That is because the caffeine goes into affect way before alcohol. Once you crash from the energy, you're at the peak of the effects of alcohol and it hits you even harder.
Drinking water throughout the night is a struggle and you will be spending more time in the bathroom than you will with your friends. The effects of alcohol make the kidneys flush everything, alcohol and water included. It's not until after detox that you can finally become fully hydrated. Eating something may make you puke the next day because alcohol messes up the lining in your stomach and you have a bunch of shit sitting in your weaker stomach now.
Taking painkillers helps with the headache, but your liver already hates you. Well, a lot more than your liver hates you. Alcohol affects every organ in your body except the organ in your ear.
Stay with clear alcohols to have less of a chance of a hangover.
I know I'm way late on this subject but I just wanted to chime in. Hope everybody had fun!