These things are really psi balls that are 'placed' by a mental hand into your body. The mental hand you can control and make it do as you like. It acts as a normal hand.
In order to do this trick, all you need is to imagine a hand form in the air and near your body. When you imagine the hand, imagine it forming psi energy into a ball form. Using the mental hand to 'place' it in your body is by mimicking with your real hand the action, near your heart. You will gain energy back in your body. And, you may feel energized for at least half a day.
When you are imagining the mental hand holding the psi ball, thinking to it the thought, 'don't be programmed except when necessary..' and the rest of the programming is up to you. You may form the psi ball in your mental hand and state the programming or command you want it to do.
If you want an elemental power ball that projects forth the element you deem necessary to have effect another. Then program the psi ball with the thought of, 'emulate [element]', and either mentally toss it at someone or something or imagine a 'beam' shoot forth of the element it emulates.
This beam can lance forth and spear another target. What you can do to the beam, is bending the beam to your will. There is an unlimited amount of things it can achieve to your will. You don't have to use a psi ball as it can be Hara energy. Your Hara is located a few inches below your Navel and has Greenish energy.