just practice a lot but not necessarily all at one time they can get kinda burnt out and start rushing them
my only word of advice is let them carry a little more speed to do the flying changes they really can't pleasure lope into them becuase it is too hard to shift the weight and they tend to really hop up in front
my mare molly is learning them well she has them down for the most part but we're just smoothing them out I find that the more I practice say 15-20 minutes a day I think she is starting to figure it out and become more balanced
good luck!