You guys, I'm not gonna lie. I give good party. Therefore, I feel qualified to give you advice on this matter.
My one and only rule when it comes to parties is: Keep It Simple. The most any good house party needs is:
1. A well-curated guest list. Only invite people who can be trusted to be courteous (or are at least happy drunks), and make it clear that any deviance from your guest list that has not been explicitly approved BY YOU is frowned upon. I recognize that this sounds like a rule that only a hard-ass would employ, but believe me - being able to trust your guests to wander around your home unsupervised and not destroy/steal/maim things is Worth It.
2. Music your guests actually enjoy. That means songs from your collective childhood (Spice Girls or Biz Markie), shared adolescence (Blink-182 or early Jay-Z), and whatever your friends are listening to now. No matter how "bad" these bands are in retrospect, you still know all the words to "What's My Age Again?" and it makes you smile. Admit it.
3. Booze. You are responsible for "getting the ball rolling" (read: Have beer and a handle each of vodka/whiskey/gin, and a 2litre each of Sprite/Coke/orange juice) - considerate people will ask if they can bring anything. Your answer should always be, "I dunno, booze I guess? Whatever you like to drink." You have a favourite drink, yes? But sometimes people don't have tonic or grenadine or your brand of gin. If you bring it yourself, you guarantee your favourite drink will be there. This logic applies to your guests. Also, this allows for interesting beers to show up at your party. People don't usually begrudge this small allowance, as it merely requires that they drop some pocket change on the way to your house.
4. Food. Unless it's a dinner party, people will be really impressed that you have those little eggrolls that you make in the oven. Get thee to Costco and buy like three different items (the aforementioned eggrolls, chips/salsa, veggie plate w/ dip - there, I made your list for you). Put cook-able items in the oven like 25 minutes before you think people will actually start to arrive (then they will be done - nice and hot - when people are actually there to eat them).
5. You. This is your party, and these are your friends!
Do: Keep in mind the reason you thought of having this party in the first place.
Don't: Spend the evening hovering and worrying - you already did the work by organizing this event, and people will feel kinda guilty if you don't seem like you're having fun.
Set everything in motion (remember your eggrolls and get them out of the oven!) and, when it comes time to party, enjoy it!