You've made it to your first big party.
How'd you get here? Maybe that wealthy preppie kid a town over is throwing a rager or maybe you finally got in with the guy who's swinger parents skip town every weekend to mix it up in el Caribe with the natives. Doesn't matter. You're first party can make or break you as a person in high school. You need to be prepared.
Have a good cover story and a place to park your car where your parents won't see it. Also, you need to invest in a sober driver or be able and willing to walk back from this party on your own two feet. You have no idea what could happen at this party, so don't count on staying over - have a backup plan in place. Driving after drinking is not a backup plan. My lawyers tell me that I can not endorse driving under the influence, so don't do it. The fines and medical bills could put you in a financial hole the rest of your life (that means you will not live the dream and you fail at life).
Odds and Ends
Never be without a few key items.
-Cigarettes (does not matter if you smoke or not)
-Cell phone & car charger
-Knowledge of good & current music
These items are the most asked for items at parties. They can help start conversation; it's a good social networking tool. This way, if Johnny Football Star comes up and can't open his beer, you can help him out while gaining style points for being prepared.
Try to bring something to the party that distinguishes you. When I worked in the dining commons of a female prep school, we'd make hot wings every friday night before we left. At whatever party I decided was the best for the night, I'd bring the wings to the drunk kids. Instant popularity and drinks for me. Try bringing some kind of different micro-brewery beer, a funnel, expensive liquor, or maybe have ping pongs balls with you. The point is to make a statement. Remember - you're the fucking man and everyone should know it.