Everything we do on the floor, should correspond directly with what we do on the ice. It must be "sports specific. " We can learn a lot on the floor. When on the ice we should try to see things from all different angles, to be able to spot where our problems are. Off the ice it is easier to focus and study where we are without tearing around at speed. We can then take these feelings and use them when we get back on the ice. There are also many “on ice exercises” for jump preparations, which compliment and correspond directly to all those off-ice exercises! The Russian trainer e.g. Rafael Aritunian is exceptionally good at these particular kind of exercise and it was he who I had work with me at my "Skate of the Art" summer camps in the UK.
It is so vital to learn the right way from the earliest possible stage of development, if you are going to aim for the elite end of the spectrum. This way there will be less trial and error. Incorrect technique can only get you so far. You could find you come to a stand still or become inconsistent when reaching a higher level. You could also be bothered with injuries because repeating a slightly incorrect misaligned movement, over and over again, can eventually become a chronic injury. Smart practice produces good results and tons of confidence. Trying to limit the amount of repetitions of a jump during learning and ending on a good note, is a good thing to avoid disappointment and injury. When a jump is not working, go back to the preparation itself. Using a harness is often a good help as well as doing some off ice jumps at this point instead of pounding away at it on the ice. When you go back on, you may feel more stable and focused on what it is you need to do.
I believe it to be very beneficial to learn jump rotation ahead of time to enable us to cope better when the time comes for those multiple rotation jumps on the ice. The skater can be taught to learn to differentiate between each quarter - half - one turn, right up to triples and quads, so there is little confusion about where you are in space.
It is important to have exact, simple and correct instructions from your coach for jumps! As I mentioned earlier, you are only in the air more or less than half a second, so don't get crossed lines about what you are supposed to be doing.