if you are hungover then fuck it, it will take a atleast a day to recover, I prefer to avoid the Hangover
A: by not drinking to much
B: If i must drink alot i will be sure to drink heaps of water before sleeping, I stay up as late as my body will allow me to, passing out means no sleep = waking up feeling fucked up.
the key is plenty of water to replenish and flush out the liver.