Scatter Chinese paper lanterns around the party room. If you can locate a paper dragon, hang it on the wall, or suspend it from the ceiling. Use a red table cloth, and place more lanterns down the center. Use red, black and white for the streamers, balloons and other decorations. Set up a small table to put temporary dragon tattoos on the guests during the party. Make a sign that says "Welcome to the (your child's name) Dojo".
Serve chicken wings in sweet and sour sauce, mini egg rolls and fortune cookies to keep the Asian theme of your party. To emphasize the healthy angle of martial arts, serve fresh veggies and cut up fruit as well. To make a gi shaped cake, bake a 9x13 sheet cake in the flavor of your choice. When the cake is cool, take it from the pan, and place it on a platter to decorate. Cut a V shape from the middle of one of the short ends to make the shape of the uniform shirt. Ice the cake in white frosting and use chocolate frosting or black licorice to create a black belt. If your child is currently taking Karate, you can use a fruit roll up in the color of the belt he has achieved.