An Educational Experience
Lesson 1: Ball Slapping
This is the safest form of testicular pain. Even blue balls do more harm to the testicles than slapping. You are no more likely to hurt someone's testicles when slapped than you are to hurt someone's stomach. Although the stomach can take more direct force, the testicles can swing back redirecting the force allowing them to take just as much force. If the testicles are held down so that they cannot swing back they will not be able to take as much force. The slaps would then have to be less than 60psi to avoid damage. Nobody on earth possess enough strength to slap someone with 60psi of force. The hardest slaps you can muster will only be about 10-20psi. This means that the chance of hurting the testicles because of slaps is non-existant. You could theoritically slap the testicles over and over again indefinitely without risk of injury. Realistically, you would hurt your hand after awhile.
Another form of this method is called ball flicking. It is done by flicking the the finger into the testicles. This is usually done while the testicles are held. The psi achieved while ball flicking is even lower than ball slapping and it also possesses no risk to the testicles.
When you are ready continue on to lesson 1's exercise.