Rider, Melynnda Thiessen, with correct positioning, initiating a circle in canter.
For more on canter skills please see https://dressagesnob.wordpress.com/2013/06/19/how-come-i-can-ride-trot-better-than-canter/
The aids to canter are fairly simple, particularly if you think of them in stages.
1. It is important not to surprise your horse with the canter. The horse, as in many transitions and movements, should know what he is going to be expected to do very slightly before he is asked to actually do it. This helps maintain relaxation in the horse–a sort of “Ready? Set? — Now proceed!” order of things.
How the aids work.
Preparation: practice positioning your horse’s head and hind leg very slightly to the inside at the same time. Rider’s outside leg is ready to go back, weight centered, outside seat bone positioned slightly back–and therefore the inner slightly forward–inside leg in a natural, at the girth position. Do this first in walk, then in trot.
Take your time here. If the horse is not comfortable with the setup for any movement you can never get the balance to have things go smoothly. Practice this until your horse is comfortable, even if it takes several training sessions. If your horse knows canter he will probably try to offer it to you when you first take the hip back. Say thanks, but not yet. It is important for the horse not to leap to canter in a hurry, but wait until you say, “Now’s the time.” That’s how you eventually get an accurate transition placement.
(Note: in the end the canter transition should be perfectly straight, but we are talking the most basic form and you are trying to make it easy for your horse. The double inside positioning of leg and poll helps him understand. You can become perfect later, for now make it simple for your horse to understand.)
1. Rider’s outside leg slides slightly back, outside side of pelvis back, inside side of pelvis downward and forward, weight centered, inside leg at girth. (You will note this is similar to getting the horse to double position–the difference is it is just a positioning of the aids–no pressure is applied.)
2. Pause a moment attracting your horse’s attention with a half halt.
3. Stretch upward through your sternum slightly accentuating the forward/downward push of your inside seat bone–not a shove!–outside leg gives light pressure, inside leg more pressure. Tip: it helps to look over your outside shoulder to position your inner hip forward. The horse should canter. If not, half halt and repeat the aid.
Green horse tip: If a young horse trots off faster before cantering, repeat the aid rhythmically until it “falls” (we hope not literally!) into canter. Again, you are not striving for perfection, just getting the horse to understand the gait. Wrong lead? Don’t worry about it, ride that lead. If you stop your green horse because of a bad transition it will not have experienced canter, so there is no way to reward the poor creature. Don’t worry how much canter you get. If the horse loses balance and has to trot, go with it for now. Better yet, if you feel he must trot, ask him to do so. We can fix this later. If it feels fun for the horse, say “more!” direct and support where you can.
Insisting on a lot of canter when the horse can’t balance and you can’t help, gives you a frightened horse galloping to catch his balance. This is not going forward, or as Rudolf said, “just running”–not what we want to encourage. Use your feel.
A note here about utterly green horses. Many advanced riders, used to a horse responding to the half halt in canter, will unintentionally kill the canter in a young horse. Oddly, green riders are not so inclined to do this–not really knowing how to half halt! There are many occasions when just cantering on is indeed the right decision with a young horse. Again, use your feel. If it seems fun for the horse it probably is. You can always circle on landing in trot to regain balance.
Basic level horse tip: the horse takes a fast step of trot before cantering, kindly say “No thanks” half halt, regroup and ask again. Be careful you are not carrying the “young horse ride” into this older horse transition. A young horse should have minimal restraint in front until it knows to “go forward, no matter what”. But it is actually much easier for the horse to balance if you regulate the rhythm and give direction in front. Be there for your mid level horse.
Upper level horse tip: Even an upper level horse will “fall off the cliff ” in a canter transition if the rider does not half halt, or as riders are inclined to do in this moment, gives no upward direction at all.
Common problems and solutions:
Nothing happens when you ask: Solution, be very sure your aids were clear. If you are sure, then short kick, says, “Think about it!” Set up again and ask nicely.
Horse kicks quarters in, does not canter: Be sure you have not applied too much outside leg–he may honestly think you want a leg yield. Correct yourself first, then correction as above.
Horse leaps to canter: Be sure your setup was methodical and clear–don’t attack the horse with the aids.
Advanced horse raises head in transition, inverting: Keep in mind this is natural for the horse–they can use the muscles that connect the poll and shoulder to haul themselves forward–jerking the head up. We prefer they use a different method. Position the horse a bit more at the poll before the transition, and increase that positioning during the transition. This will not work unless your outside side is back and controlling the outside hind leg from stepping out. The inside positioning must connect with the outside hind leg–line them up.
Haunches swinging: (I told you I was going to get to this). A common problem in upper level horses is that the horse positions the quarters too much to the inside. This is usually caused by the rider using not just a positioned outside leg, but a really active outside leg. Don’t do this. Swing the leg back softly, positioning your body as above, then ask mainly with the inside seat and leg as you half halt and think of balancing uphill.
When in doubt go back to the training scale. Do the most basic and obvious things first. This is not complicated. Take time to figure out the root of the problem.
Rider, Melynnda Thiessen siting nicely “upward” assisting the young horse to maintain balance.
For something that does work, and will cost roughly three riding lessons, not three months of training, improve your girthing strategy.