I'll be honest with you cause you've come in here and had the balls to pose a serious question, so imho you also deserve a serious answer ...
1) on your first day drinking alcohol, stay away from the heavy stuff....
2) drink preferably beer, its the cheapest and most common, you wont really enjoy the taste at first, but it'll grow on you...
3) don't keep drinking until you feel drunk/hazy, alcohol takes some time to kick in, if you stop or slow down when you start feeling weird, it's already too late...
4) don't be shy of drinking water or soda in between beers, drinking 4 beers or drinking 4 beers and 2 waters makes a huge difference ! you'll feel much fresher if you mix it up with some non alcoholic stuff + you'll be able to take more too ...
5) Don't let anyone talk you into doing something you don't feel like doing, if you ask yourself; "is this a good idea?" when you're drunk, the standard answer is; NO, its not a good idea...
don't get wrecked and do stupid shit you'll regret later on, even tough those stories are funny to hear, they aren't funny for the person(s) involved .....
-Peace out and be careful !