There are some steps you can take to drink hard liquor and not regret it in the morning.
- Pick a drink and stick to it.
Get to know it intimately and let your body become accustomed to that particular combination of toxins. If you drink enough (I'm talking long-term, here, not on any given binge) you can increase your drinking vocabulary (as it were) to encompass multiple drinks. Don't try to take on the whole spectrum - pick a clear (gin, vodka and some rums), a brown (scotch, whiskey and the rest of the rums) and a liqueur (baileys, goldschlager and the like) and spend some quality time with them. You won't regret it.
- Don't take shots.
Seriously. Pick something relatively normal: G&T's, vodka tonics, scotch and sodas, whiskey sours. Shots hit your system much harder than the more subdued drinks do and are more likely to turn you into a belligerent asshole. Besides, you'll look much more sophisticated with a highball glass in your hand.
- Moderate yourself.
It's always good to go out drinking with someone who drinks slower than you; they tend to keep you in control by forcing you to wait before someone picks up the next round. Being drunk is fine, just make sure you could, if necessary, find your way home by yourself.
Pick your brands carefully.
This is a talent. On the one hand if you drink the good stuff you probably can't afford to drink much of it. On the other hand most house brands are kinda gross. House scotch and most house whiskeys should always be avoided. House vodka usually isn't too bad, particularly if you're mixing it with something - the stuff is designed to have minimal flavor.
The stupider the name, the worse you'll feel.
Look, I know you think it's cute to order a slippery nipple, a slow comfortable screw up against the wall or, so help us, a screaming purple jesus, but the fact is it won't be nearly as cute the second time around. Plus, mixing hard liquors is a surefire way to introduce yourself to mister hangover in the morning.
There you go. Assuming you follow all the normal drinking rules (keep hydrated, no driving home, etc.) I can almost guarantee you'll fare much better in the morning. Oh, and while you're trying to keep all this straight in your head the next time you belly up to the bar, don't forget to enjoy yourself.