I reccomend to start both exercises in trot. It is esasier to start with “Egg yolk”- ride 20m circle in trot and inside the circle in the same direction ride smaller circle (10m) in trot. When the trot is balanced- do transition to the canter in 20m circle after 10m trot circle. In “Snowman” - You change the direction from one circle to the other. First ride the “body” of the snowman -20m circle, then - change the direction and ride the “head” -10m circle in trot. Then - after the “head” in trot, ride the “body” in canter. This exercise is helpful for horses at any level. For green horses - a helpful way to get the correct lead in the canter. For the horse who tends to bulge its outside sholder, “snowman” is helpful to ride in the direction that the horse bulges its sholder. For example: if your horse tends to bulge the outside (Right) sholder when tracking left, riding “head” to the right lets Tou bend the horse right and push him out off Your right leg. Then as You come back to the “body” riding left, the horse should be more respectful to Your right leg and not bulge out as much. This will help to get a better canter depart, because You can keep him netter balanced “across” its shoulders. You could play with the flexions (inside/outside) in these exercise, too. Joyful riding🤩