|It actually kinda looks like this|
The materials you will need are: three ping pong balls, scissors, tin foil, a small screwdriver or pins, tape(optional), and a sparkler.
The first thing you are going to want to do is to cut a small hole in the top of one of the ping pong balls. The easiest way to do this is to poke a hole in it with a screwdriver or pin and then make it larger with the scissors. You also want to poke a hole in the bottom of the ball as well.
Next cut up the other two balls into small pieces. These have to be small enough to fit through the hole you made earlier.
So now that you have more ping pong ball fragments then anyone should ever have its time to insert these fragments into the ball you cut a hole in before.
Half way through adding the fragments to the ball it is now time to add your sparkler. To do this place the wire side into the big hole and out through the one on the opposite end. In case you are wondering, the sparkler acts as a fuse. Now continue adding the ball fragments.
Now bend the wire from the sparkler towards the top of the ball so that it touches the other side of the sparkler. Wrap the wire end of the sparkler around the opposite side of the sparkler.
Now its time to wrap this in tin foil. This doesn't really require any special methods to be effective, just make sure that the foil is wrapped tightly around the ball. You can use tape to secure the foil, but in most cases this should not be necessary.
Any there you have it, your own homemade fireball at your disposal. Just be careful because once this thing has been lit there is no stopping it and eventually it will erupt into a small ball of fire. Also keep in mind that this is fire so use common sense when using. I am planning to post a video demonstrating this in action, and hope to have this up this weekend.