Dont charge for girls no one will come, and dont throw a party with your parents gone unless you have a lot of good friends to help clean up. Me and my friends did this and people will throw up, people will steal your **** no matter how much you know them, and people will break stuff. You should move everything out of the rooms people will go in and lock them in a bedroom. Have signs posted with arrows to the bathroom. Get a 15 gallon keg if possible. This is about 170 12 ounce beers, this cost about 50 bucks to fill up and however much to rent it if you cant get one. Also get some bottles of some hard liquor, mainly captain morgan and some cheap vodka. Peach schnapps is also not a bad idea.
Have it be free for girls no matter what, and for guy have it bring a bottle or 5 bucks a person. Also you need a good mix of music, try to avoid rap and stick to hip-hop, this will get the girls dancing and thats a good thing and will loosen up the mood. You cant let people park in front of your house, you need to have them disburse their cars among the neighborhood roads as far away as possible. If cops come make sure all people are inside, they cant come in unless they see a crime being committed in plan sight of the doorway. So dont step out cause the second you step outside the door sill you could be arrested if you doing anything wrong.
A party with no beer is a gay party, even if you have weed. Plus 40 people is a hell of a lot more people than you think when it comes to a house party, so invite about 30 at least a week ahead of time, and see how many of them plan on coming, because if you invite 15, then 30 will come becuase they bring friends. So invite 30 and probably 20 will say their coming, which means 40 will show up.