To see your stride coming you need to practice! The more you'll try, the easier it'll get.
But there are some exercises you can do to help yourself.
For example, put two ground poles separated from 5 strides, count them out loud and when you "see" them coming you can try to put one less (4 by pushing a little more your horse) or one more (6 by keeping him with you).
This is the best exercice to help you with your problem, i hope it'll work :)
You can also work on combinaisons lines (you will know how many strides are between the obstacles and it will be easier for you to feel them) or even put a ground pole one stride before the jump to feel the moment your horse starts jumping.