I learned a few things from hosting and going to such parties and I would like to take this time to share these small bits of wisdom with you.
1) Know your neighbors
Nothing will spoil a good party like neighbors. Before planning to throw those "my parents are away" parties you need to take a careful look at your neighbors. Ask yourself these few quick questions:
a) Are they friendly with my parents?
b) Do they talk to my parents often?
c) Will they be home when the party happens?
d) Are they likely to call the cops?
e) Do they hate me?
If you answer yes to any of these questions you might want to rethink your party.
Most important, if you live in the same building as your landlord DO NOT throw a party!!!
2) Be mindful of the guest list
Don't hand out flyers at school, that only works in movies.
You need to know who is coming to your party. Invite people you trust and ask them to keep added guests to a minimum. You do not want a situation where strangers are in your home.
By only inviting people you know and trust you avoid the problems that can occur when something ends up broken or stolen.
Nothing should be stolen when friends are invited but things do get broken sometimes. With friends involved you can quickly work out a way to replace the item or fabricate a good story as to how it ended up broken without telling your parents about the party.
3) BYOB
If you are hosting your friends should be supplying. No money should have to leave your hands to fund the food and drink involved at the party.
With that said, you should provide plastic plates, cups and cutlery if your party is going to need such things. You don't want to end up with a sink full of dirty dishes in the morning. By using plastic/paper items you can dump them all in the trash and have one of your guests remove the filled trash bags to a dumpster far away!
4) Be mindful of things with memory
At one of the parties I went to in high school one of my friends had a full size Centipede arcade game in his dining room. It was a gift from his dad to his mom as she loved the game.
All of the top high scores had his mom's initials on them... Do you know where this is going?
Early on I found the book with the dip switch settings in it so, with his consent, I changed some of the settings to give you more lives and lower the points required to earn extra lives.
The next morning he went over to the machine and about had a heart attack! All of his Mom's high scores were gone to be replaced with insane high scores and three letter attempts at cuss words.
He pulled the plug on the machine but the scores did not reset. He pulled out the book looking for an answer.
I think we ended up clearing all of the high scores from the machine. I'm not sure what he told his mom about why her scores were gone...
5) When cleaning, clean the whole house
I remember one day when I stayed home sick and my older brother decided he didn't want to go to school that day. He and a friend of his showed up back at the house about an hour after school would have started with a bottle of schnapps.
An hour or so later someone was blowing chunks on the kitchen floor.
They cleaned it up, but only that one spot.
Because the kitchen floor was old and the vomit had alcohol in it that one spot looked mighty clean compared to the rest of the floor. In fact, when my mom came home that evening she knew something was wrong because the floor had this one large clean spot on it while the rest maintained its usual old and dingy appearance.
6) Mark some rooms off-limits
Remember, this is your home. It's also your parent's home.
If there is an area of the house you do not want people going into mark it as such and lock the door if possible.
You don't want to stumble in on Jane and Dave in your parent's bed. You don't want to stumble in on them in your bed either!
The point is that you need to inform the people as to which areas of the house are off limits.
7) Sleep space
Odds are that some people will want to crash at your place, this is a good thing. It's much safer to have them wake up groggy the next morning than reading about them having died in a car crash in the morning paper. Besides, anyone still there in the morning has to help clean!
8) Cars
Nothing gives away a party like seeing twenty cars in your front yard. Tell your friends to car pool, as many as will fit in a single vehicle. If someone has access to a van invite them.
Most of the parties I went to had a maximum of 40 people present but not 40 cars. You can squeeze five people into most of today's cars and that would work out to about eight cars, which is still too many to have out front. You want to keep extra cars to a minimum, aim for five or less total cars in the yard. If you live far away from most people this is not a problem. If you live in an apartment building it's also not much of a problem but if you can fit 40 people into your apartment you can probably afford to rent and empty studio instead!
9) Alcohol
It is very important that if your party will be serving alcoholic beverages that you understand a few things.
a) What is the drinking age where you live?
b) Will there be designated drivers?
c) If someone drinks "too much" do you have emergency numbers handy?
Serving alcohol to minors is illegal in most areas. Be aware of the laws where you live and if you should see flashing lights in front of your house and a heavy knock on the door try to remember that if you allow law enforcement in they don't need a warrant.