Plan kind some type of beginning, middle and end for the party.
Even a few minutes are a long time for kids, so begin activities 15 minutes after the party commences.
Crafts make terrific activities--making a little hat or decorating a mural, or something else that goes along with the theme of the party.
Avoid tears and tantrums by adapting games so everyone gets a chance to win a prize. If you wanted to Pin the Tail on the Donkey, make sure there is a prize not only for getting the tail in the right place, but for the tail that is the farthest way, the tail that's in the funniest place and so forth.
Plan more games than you'll possibly get to. That way, you can easily switch to a new one if the current one is bombing. And don't be afraid to repeat a game if it's a hit. It's the kids' day so let them do what makes them happy.
If professional entertainment is on the agenda, have the show start 30 minutes into the party to allow for tardy guests. For the young ones, a guitar sing-along is really good. The kids love music, and it's even better if the singer brings along some little instruments so that the little children can play along.
If you've got your heart set on hiring Bozo, keep in mind little kids are often scared of clowns. One way to avoid that: Let the kids watch the clown put on the make-up.
Preschoolers love interactive entertainment like puppet or magic shows.
The best entertainers are the ones who involve the children in the actual show. The magician can teach them a little trick and then they perform in front of their friends, and this makes the birthday child feel special.
Don't hand out noisemakers until after the show. They can distract.
If a pro isn't in the budget, don't despair. Get creative. See if your local fire department will swing by with a fire truck or perhaps a friend at a local farm or a child or a teenager who has a horse would bring it to the party. Or hire a teenager or a babysitter for the day to paint nails or do French Braids or something fun like that.
Consider renting a party activity. Moonwalks, ball ponds and dunk tanks are all good bets. You can even rent things like popcorn carts, Sno-cone makers and cotton candy machines.