Before shooting, you need the correct stance and the correct way to hold the string. The weight of the entire body should be evenly divided between the forward and backward feet. The abdomen should be tight. If the abdomen isn't stretched to its fullest, it'll cause a loss of balance due to the haunches being pushed backward. The abdomen is naturally strained by standing with power in the legs.
Correct breathing is essential.
Take a deep breath, then release it slowly, emptying your lungs. The neck should be held as straight as possible. Now you should put on your thumb ring. Draw back on the string with it resting against the ring. Wrap your index finger around the end of your thumb, as though you are going to flip a coin.