My usual hangover remedy is a big helping of instant ramen noodles and a giant sports drink (Gatorade or similar – something with electrolytes). I have no idea if there is actual scientific evidence supporting this meal choice, or if it’s just a psychosomatic thing, but it tends to make me feel better.
If you need to drink some coffee (or another caffeinated beverage) in order to get through your day, make sure you balance it out with lots of water; hangovers are caused by dehydration so you’ll just exacerbate your problem if you chug a ton of dehydrating coffee.