The best thing I have dine to harness and take control of myself and mind was breathing exercise, it's a type of meditation, but it's much more than that. Once you master it you can slow your breathing down, stop hyperventilating, and even slow your heart rate down. Google some for beginners or on youtube and just keep going with it. The most important part of any breathing exercise is to brath very slowly, count your breaths, and in through the nose and out the mouth.