Hold the tuba upright as if you were going to play. Tilt it forward slightly.
Pour one-quarter cup of dishwashing liquid into the mouthpiece. Pull the tuba back to an upright position once the liquid has entered the tubing.
Place a cloth on the end of the mouthpiece and turn the tuba in a circular motion with the mouthpiece pointing towards the floor at about a 45-degree angle. This will evenly distribute the liquid inside the lead pipe and around the mouthpiece. Since a mouthpiece curves inwards, the soap will seep between the mouthpiece and the lead pipe creating lubrication necessary to remove the mouthpiece.
Twist the mouthpiece to the right or left and simultaneously pull the mouthpiece out of the tuba. It should come loose at this point. Rinse the lead pipe using your regular cleaning routine.
Lay the tuba down on its front. Be careful to avoid damaging any of the valves.
Set the mouthpiece puller on top of the lip of the lead pipe with the other end attached to the rim of the tuba mouthpiece. The tuba mouthpiece will pop out from the pressure of the tool.