Essentials to throwing a party

Food is a definite at most parties. It doesn't have to be a full course meal or anything. But items like pretzels, chips, etc. are great ideas to have at wherever you are having the party.

Drinks.
Also be sure to have plenty of waters and sodas. Depending on the type of party you are having, you may also want have alcohol. It is better to buy too much than not enough. Because if there is nothing to drink or eat, sometimes a party can really die.

Music.
Choose your music accordingly to the type of party you are throwing. You are going to need more than just an mp3 player. Try getting a stereo or borrowing a friends.

Pick a theme.
Themed parties can be a lot of fun. When searching the web you can find many ideas that other people have done for parties. Or if you are very original you can maybe think up something special for your own.

Send out invites.
Possibly do an RSVP. That way you will know how much food and drinks you need to buy. And also hopefully this way you will avoid having random guests show up at your house. Doing this is a lot safer than just sticking flyer's up around town.