This is an excerpt from Archery by USA Archery.
Achieving Set Position, Posture, and Mindset
Finally, after setting the hook and grip, you are ready to complete the set position. Set can also be described as the A spot of each shot (see figure 4.17) because it is the end of the preparation portion of the shot cycle before any major movements occur. After you set the hook and grip, look up, prepare your torso, and confirm that your stance and posture are correct. Set your head position and shoulder alignment so that your shoulder is approximately 60 to 80 percent in line with the target. Your head should sit over the ball of your back foot, thus helping to provide the 60/40 ratio of weight distribution on the balls of your feet, and must not sit over your spine, helping you to maintain a flat back and some tension in your lower abdominal muscles. It is also important that you feel a small amount of tension in the lower trapezius at the final set position.
Now that you have set the physical foundation, make the final preparations before raising the bow. Mindset refers to the final mental preparations you make prior to committing to the shot process and is the final part of the set position. Now, select the point of eye focus (i.e., location on the target at which to aim). During windy or rainy conditions, aim at a location on the target other than the center. In these weather conditions you must judge how much to aim off based on your experiences. Once you have fully committed to taking the shot, move to the setup position.
Achieving the Setup Position
Setting up refers to the movements you make to achieve the setup position. Once the set and mindset are complete, raise the bow to setup position. The main goal of the setup is to set the barrel of the gun while maintaining the grip and hook positions and having your drawing scapula close to your spine. To raise the bow to setup position, initiate the movement at your bow hand. At the very beginning of raising the bow, your bow hand must raise the bow in an arcing fashion, with your bow arm extended as far away as possible from your body (see figure 4.18). Your drawing arm is merely connected to the string and is raised by this connection and not by your manually raising it or your drawing hand. Raising the bow in this manner causes the stabilizer to point up and your drawing hand to be at a lower vertical position than your bow hand at setup. As you raise up, the sight should not be in line with the target. If you are a right-handed archer, your sight should be pointed to the left of the target at the final setup position, thus preparing you for angular drawing (the position will be the opposite for a left-handed archer). You should be able to see the target slightly through the riser and string.
As you raise to setup, maintain the position of your drawing forearm and wrist, and the hook and feeling of the steel chain. You should feel an increase in the tension in your lower trapezius as you rotate your chest to set the barrel of the gun. While you raise to this final setup position, take an “extra set” to create the bone alignment to achieve a perfect barrel of the gun. The extra set motion requires you to twist more at your midsection, above your waist, to get your shoulders and chest to set the barrel of the gun. Do not roll your bow shoulder forward or try to set your drawing shoulder back to set the barrel of the gun. The alignment from the pressure point of the grip through your bow shoulder to your drawing shoulder should be set from rotating only the torso away from the target. The torso rotation sets the barrel of the gun (see figure 4.18). The most important philosophy behind these steps is to create a foundation for angular drawing and loading. With angular movement, you use more efficient torque of your body's pivot point. If you are new to this setup you might have a tendency to exaggerate the position and movement. It is important to remember that the motion from set to setup should be a smooth, natural movement and not be exaggerated. If you exaggerate the motion too much, you might not be able to easily set the barrel of the gun. See figure 4.19a for an example of correctly setting the gun and figure 4.19b for an incorrect example.