The lead hand hook is tough to learn for a lot of reasons, but the piece that seems to burn most beginners is the pivot. To generate the most power, it is important to shift your weight from the front foot to the rear foot as you throw the punch. The most efficient way to do this is to pivot your feet. Learning the strike from stationary helps. Start with the majority of your weight on your flat front foot. Be up on the ball of your back foot. Then, as you punch, pivot. After striking, you should be up on the ball of the front foot and flat on your back foot. Practice this a ton from stationary first, and then when you feel like you’ve got it, add in some footwork.