hi ana! with my horse i make a troting circle then, cut through the middle and when I'm turning I asked for him to Cantor. It helps with his muscles and will improve him for picking up the leads etc.
Speed changes! It improves the quality and balance of the canter. When you can do speed changes good on a volt you can start working on pirouettes. You don't need to actually do pirouette, but I experienced just beginning on them improves the canter a lot.
Hi Ana, with my horses, I find working up there muscles helps there canter a lot, so I like to do big canter circles and canter rides up and down hills to help them carry themselves a little better. hope that helps 😉