The walk is a regular four-time movement and the horse always has two hooves on the ground. The horse lifts his hooves as follows:
(1) Foreleg, (2) Diagonal Hindleg, (3) Other Foreleg, (4) Remaining Hindleg.
The trot is a steady two-time action. The horse moves opposite diagonal legs together and changes from one pair of legs to the other:
(1) Right fore and left hind, (2) Then left fore and right hind, or vice versa.
The canter is three time movement. The sequence for the canter is:
(1) Either hindleg lifting, (2) The other hindleg and its diagonal foreleg together, (3) Finally, there is a moment when all four legs are in mid-air.
The gallop is a variation of the canter, but the legs move one at a time. It is a four-time action.
There are two gallop sequences, (1) Either hindleg lifts, (2) Followed by the other hindleg, (3) Its diagonal foreleg, (4) Then the remaining foreleg.
HOW TO SIT IN A CANTER
The position you should be in for canter is much the same for the sitting trot. However, because the canter is a faster movement, you have to be more careful about getting your position right. Any mistakes are accentuated.
Look ahead and only glance down briefly when you have to check the leading leg.
You should sit back in your seat, but don't tighten up too much - try to relax your seat and lower back muscles without loosing your position. You must remain firmly in the saddle. Rock gently with the rhythm of the canter. All the movement should come from the small of your back.
Make sure your heels are lower than your toes. Push your knees down into the saddle .