1. Collect all materials needed to construct your cannon.
2. Take one of the tennis ball cans and cut it in half using the pair of scissors you collected.
3. Then take one of the tennis ball caps and cut a small circle in the center of the cap.
4. Using a small amount of duct tape to connect the two halves of the bottle, placing the cap with the small hole in the center so that is separates the two halves.
5. Taking the other tennis ball can lid, cut it so that you get a half circle piece.
6. Then take the remaining portion of the left over bottle and cut off the metal ring at the top.
8. Punch to small holes in the bottle of the barrel so that the two half metal rings can be inserted.
9. Then take the half circle piece of the tennis ball can cap and attach more towards the top of the barrel as shown in the photo.
10. Adjust the legs and plastic to make the barrel be directed in a 50 degree angle.
11. Finish securing any loose pieces with duct tape.