As a Dressage rider, your seat is paramount. All of your efforts to improve your horse(s) will be futile, unless you possess a good seat, as you will not be able to give your horse clear and precise aids. Learn HOW you should be sitting in the saddle.
In the sport of Eventing, ensuring that our horses are truly fit for our level of competition is one of the best ways to prevent unnecessary injuries.
Control the tone of the voice in your head when you are riding, as if it becomes irritated or harsh, your horse will feel it and become tense. If it becomes timid or uncertain, your horse will feel that and may either become timid and uncertain himself, or he may
"Ride around the corner in an active, short canter, and let your horse do the jumping." ~ Andrew Nicholson
Learn about the ONE very basic exercise that the all of the riders had to do at the USET training sessions down in Ocala, that proved to be very challenging!