You're almost there, go on
Set 5 minutes on your timer
Stay seated as you are, with the balls resting on the surface.
Place your hands on top of each other over your balls, with the palm crushing them against the hard surface.
Start to squeeze, put all your strength, all the weight of your body, lean forward with your back to make sure you use all the weight, lift your legs do not touch the ground, balance on your balls.
have a good time