"Kegger"? You mean a party with kegs? Never heard that term before.
I don't have any tips on how to get laid, but if you want to get good social proof buy a case of beer and take it with you as a gift for the house. At parties like those, the person who controls the alcohol usually has social power. I know this because I've done it in the past. Take a case and spread the love. You'll meet a lot of girls and get invited to more parties. Just rinse and repeat. Taking drugs is cool as long as you have enough to go around. Don't get high, meet a bunch of girls, and then not have enough for them. Girls love cocaine. They will do lots of amazing things when they know you are the man with the connection. Weed is not nearly as cool. If you know where the cocaine is at, you will have an endless supply of girls. Or, as LMS would say, hors.
I think parties are cool up to a point. When you start getting invited to a lot of parties, then you become the one that people call up to ask where the party is at. Then you have a level social power, and because you know a lot of people and people know you, you can get laid more easily. You can also get almost any drug you want by just calling up a few people. Just be careful not to go overboard and kill yourself. It's easy to get addicted and messed up.
But then again, that's what I used to do. Not really my thing any more. But it is your first time, so you should experience it. After a while you'll get tired of that though. Have fun.