I’m right there with you, so here is a step-by-step guide to your hitting approach that, if practiced diligently, can improve your kill percentage and give you another inch or two on your vertical.

NOTE: This guide is for a three-step approach because that’s the most commonly used. If you’re using a four-step approach simply add a small step to the beginning of this routine.
1. The First Step: Left foot (for righties – lefties reverse all of this)

This step is the one that needs to cover the most distance for your approach. It should propel you forward toward the net as fast and as far as possible.
During this step your shoulders are turned in facing the setter, and you are bringing your arms around behind your back by making a wide circle in the air with your hands. Both arms should move in unison and they should remain totally straight during this step. By the time your left foot hits the ground your hands should nearly have completed a full circle; they should be nearly behind your knees at this point.
2. The Second Step: Right Foot

Your right foot step helps stop your forward momentum and begins to transfer it into upward momentum.
This step is MUCH smaller than the first one. You should be practically into the right position to jump and hit the ball at this point.
The arms continue their circular movement, coming around past your knees during this step. Here you also begin to close your body toward the net.
3. The Third Step: Left Foot

Your left foot should land basically parallel to the net in order to almost completely stop your forward momentum.
But you don’t want to lose all that energy, you just want to switch it from forward to upward. To help this process we have the arms, which have now gone in a full circle and are propelling you upwards.
4. Step Four: Swinging

Don’t neglect your arms when doing your approach. They are just as important as your leg strength when jumping, but many people don’t focus on their arms and as a result don’t jump as high as they could.
Both hands should extend above your shoulders; your off-hand (the one you don’t hit with) remains fully extended above your head to spot the ball. This helps make sure you’re in the right place to hit. Your hitting arm is pulled back, with your hand near your ear, cocked and ready to swing.
As the ball comes into range, use your abdominal muscles to pike forward as you swing your arm to hit the ball. If you’re going for a line shot you need to close your body as you swing so that your shoulders end up facing where you want the ball to go; for a cross-court shot your shoulders remain at an angle with the net.
Snap your wrist and swing through the ball in order to hit it down and not send it flying out the back of the gym.
Spend a few minutes before every game doing laps around the gym using your approach. The rhythm of the three-step approach should be slow-quick-quick. Left-right-left, jump, swing. Repeat in a circle around the gym.
This will help you get comfortable using the footwork (make sure you wear the right volleyball shoes!) when there isn’t a volleyball involved. Don’t add in an actual set until you can do the approach in your sleep.