1. DO send your invitations out TWO weeks in advance.
2. DON'T send too many out. Four kids are enough.
3. DO have everyone RSVP before that week is through so you need to know if you should send invitations out to anyone else.
4. DON'T allow siblings to attend. (This is especially important in LDS circles since one family of siblings can exceed your target guest quota.) In fact, I would even suggest not inviting the siblings of the birthday kid too . . . rarely does a seven year old want to make Mickey Mouse crafts, nor does the normal two year old girl want to play with light sabres. (I did say normal, sometimes there are exceptions.)
5. DO NOT invite all the parents. That's way too many mouths to feed. If you need help, bring one or two friends to come . . . without all their extra kids, of course!
6. DON'T clean your house too well before the party. It only needs to be clean enough for the first guest to think it's clean. By the time the rest of the guests get there, the chaos that is occurring hides any grime that might be lurking under your tables. And certainly at the end of the party you will find your house utterly trashed.
7. DO have organized games and crafts going on. This helps keep kids in the area where you want them to be, and is intended to prevent them from entering areas in the rest of your house and trashing them, or throwing toys from the top landing to the foyer below.
8. DO have help to keep the kids coralled into said crafting areas. Consider hiring a bouncer. Not only could he help with coralling, but when your guests refuse to leave at the end of the party, he can help get them out for you. ;)
9. DO hire a cleaning lady (or some really helpful in-laws at the very least) afterwards to clean up. You have done WAY too much work.
10. DO enjoy listening to your child gush about how wonderful her birthday party was; and how her favourite part was the play-doh station and the balloons.