Imagine, if you will a little walk on your own feet.
Suppose that you are going to step(jump) over a board on the ground. You start walking toward the board. As you get closer to it, you can stay the same, which means your last step over the board will not be like the others–long or short, or you can plan ahead and adjust to close the long step at the end or compress to lengthen the short step.
Now, the “move up” at the end is best achieved if, whether long or short, you compress the springs–that is, build the impulsion. So imagine yourself walking–not ambling (no attention), shuffling (no impulsion), or wildly waddling (lots of energy but no direction of the energy)–boldy up to the board. Suppose then that you close the long distance with your bold walk. Then the board doesn’t affect your walk at all. Alternatively, shorten your steps a bit deliberately and again the board makes no difference.
Maybe you have done this approaching a set of stairs, or approaching a ditch in the field on your way to retrieve Billy. This is what riding to a distance should feel like.
The key to making it look good in the ring is that the horse should be taking direction from you–compress or expand with tension in the springs (hocks).