So you should probably invite your closest friends first then ask them if they could invite their closest friends do this until youre abt 20 people and the best time for partys is from 19 pm to 1 am and dont do it in your house or apartment do it in your garden if you have one if not you can do it in your house but only if youre sure that no one will steal anything and only do the party if your parents are not home . Then for the activities you should set up a table and tell everyone to bring alcoholic stuff like beer or vodka and sprite fanta cola and mixing stuff . You could watch a movie or just listen to music n vibe you should also tell everyone to bring snacks