All you need to do any dressage movement through Grand Prix is 11 individual basic responses, cued one at a time in a certain order. Each movement is build using a different order or combination of responses.
You don’t need a fancy dressage horse to learn how to do this! Just start with the movements with the fewest basics: the half halt, and leg yield. Then move on to combining three basics with the shoulder in, haunches in, and renvers. Increase the complexity as you increase your and your horse’s ability.
Clairety Horsemanship 