In a good set you use not only your arms and hands but also your legs. The set is a coordinated action of the entire body to give you greater control and accuracy of the set. To develop a greater ability to execute these actions (which will also improve your ability to jump and block) you should do the push press.
Assume a standing position with the feet directly under the hips and with a barbell (or dumbbells) on the shoulders with the hands slightly wider than shoulder width apart. Bend the knees slightly and then as you straighten the legs push the barbell upward in an arm-straightening action. Full extension of the legs should coordinate with full extension of the arms. If you push sufficiently hard you may rise up on the balls of the feet. This is fine. However, be sure that you do not jump off the ground as this may impact the spine on landing, especially if you are using relatively heavy weights.
Inhale and hold your breath as you extend the legs and push the barbell upward. Once you achieve the upright position and the arms are fully extended, exhale and pause momentarily. Then lower the barbell to the original position and repeat.
This exercise requires strong involvement of the lower back muscles to maintain an erect position. Most players do not have to consciously contract these muscles as it usually happens automatically. If you are a novice, consciously contract the muscles to learn the feel of an erect torso with the muscles contracted. Under no circumstances should you contract the abdominals as is often recommended. Doing so will remove the normal (arched) position of the lumbar spine and predispose it to injury. However, strengthening the abdominal obliques will help prevent any twisting of the body when you do the push press.
If you use the push press to improve your jumping, then you should explode out of the bottom position as you extend the legs. In this case you should leave the ground but as you land, cushion the legs slightly and lock the arms to hold the overhead position on extended legs. Use sufficient weight so that you do not go far off the ground. The higher you go the greater the impact forces on landing that can be injurious if sufficiently great.