Instructions

Fit barrel into chamber, making sure the muzzle knife is facing out.

Select a potato that is larger than the end of the barrel.  Center the muzzle knife over the potato and apply pressure until a chunk of potato shears off, sealing/plugging the end of the barrel with potato.

Use a rod to ram the potato down the barrel, stopping 1 inch from the chamber.

Open chamber, spray recommended quantity of hairspray into chamber (see individual cannon descriptions) and quickly close chamber, being careful to fully screw on the cap.

Aim at target & press igniter button until cannon fires.

If cannon doesn't fire on 2 or 3 clicks, open chamber, let breathe, close and try again.