First and foremost, invite friends and family that you know and trust. If you're planning to get drunk on your birthday, it is best not to have people around who will take advantage of your altered state of mind. Secondly, plan a budget. Even while throwing a big bash, you can still find ways to keep it inexpensive, such as making the party a BYOB: "Bring Your Own Bottle", starting a collection pool for an alcohol run, or even brew your own beer beforehand.

Music choices will vary from person to person at your party, so you want to make sure that you have a wide selection, or if it fits into your budget, hire a disc jockey. For entertainment, there are many options that you could do. Just try to keep an open and creative mind. For example, a party I once attended, the host had painted Twister circles on the floor tile with water-soluble paint. After fashioning a crude, but effective spinner out of cardboard and paperclips, there was much fun, laughter and amusing photographs.

Since it is a twenty-first birthday party, it is expected that a few drinking games will be played. Beer Pong is an example of one of these types of games. It is a game played on a Ping Pong table with two triangles made up of six cups on either end of the table. Using two beers per side fill the cups. You should also have a cup full of water on each side to use to rinse the ping pong ball should it happen to fall off of the table. The two players of each team, taking turns, each throw a ping pong ball to the other side of the table, trying to get it to land in a cup. If it does, one of the players from the opposing team have to drink the beer from that cup. If both players are successful in landing a cup, their team shoots again. If they can sink their balls into the same cup, the game is over and all of the remaining beer must be consumed by the losing team members. The object of the game is to rid the opponents side of all beer cups. House rules for Beer Pong can vary from house to house, so you can be inventive and make some rules of your own. A good example of a house rule would be: in the event of a shutout, which is when one team makes all cups before the other team makes one, the losing team must strip down to their boxers and run around in the parking lot for one full minute.

The important thing to remember is that 21 is a special birthday, so be sure to have fun, also remember to be safe. Do not drive if you have been drinking.