One of the reasons we feel like crumpled up wet paper towels the morning after a bender is because we're dehydrated. The best way to stay hydrated? Drink plenty of water. In fact, water is your best friend when drinking. Try making your drinks weak by adding more water.
If you're dead set on having strong drinks, or drinks that you can't add water to, consider having a glass of water between each drink. This helps you pace yourself, stay hydrated and fills you up a bit, meaning your rate of consumption will probably slow as the evening, and your ability to process alcohol, progress downward.
Photo courtesy Max Mayorov via Flickr/CC