Even guys that are less than three feet tall can look cool in a tux!
The grown-ups are all really nervous. Running up and down the aisle pretending to be a race car is a nice distraction for them. If this doesn't work, try refusing to let them pin the flower on you. It'll take up some time and give them something to focus on besides throwing up.
Don't listen when they try to get you to put your toys away. People with important jobs at weddings can find time to play with their cars.
Ties suck. So do fancy shoes.
The lady with the big harp looks at you suspiciously every time you get near her tangle of cords and her stringy noisy thing. She doesn't know that you can do a better job playing it than she can, but maybe if you can get just a little closer.....
No matter how dressed up they make you get, be yourself.