Using aids properly
I, too, have had issues with using too much hand. What really works is getting your horse flexible, first, before jumping. Think of patterns you can do. For example, there is a pattern called the traveling figure eight done at the trot. Starting at one end of a ring/arena/area of pasture, do a figure eight. As you complete the figure eight, ride straight and do another figure eight, and so on. Just before you change direction, concentrate on using more of your new inside leg, having the new outside leg holding the shape of your horse. You should start to find your horse getting more flexible and lighter in front. Each time I ride, I do something different. Within 20 minutes, I change direction, change gaits, shorten and lengthen the stride, leg yield, etc. This way the horse is not apt to anticipate what you want to do. I do the same with jumping. As someone else posted, keep centered, use more leg than less (this actually works), and ride inside leg to outside rein. Hope this helps.