Pressure with jelq and clamp

I try both but I need to know the right pressure do you squeeze really tight?

Jelqing requires enough pressure to move the blood toward the end of the penis while 50-75% erect. Not so tight that you completely compress the shaft, but tight enough to feel the blood moving ahead of your grip.

Clamping is done fully erect and the clamp is applied to the base of the shaft tight enough to prevent outflow of blood. That usually means very tight (all the clicks you can give it), but make sure you protect the skin with a light wrap of some sort.