I liked these strategies for excelling mentally in the horse show ring from author Barbra Schulte

Here are my take-aways:

Let go of the fear of exposing your horse’s weaknesses. Every horse has his its less-than-perfect aspects. Instead, it’s your job to help him through difficult situations. Enjoy being flexible and responsive to the moment.
Say to yourself, “No problem” when you or your horse makes an error. This simple phrase is one of the most powerful performance tools used by world-class and Olympic athletes. It’s a basic tenant of the “mentally tough” philosophy.
Do your homework prior to the competition.. Rehearse in your mind how to handle a situation if it arises. If you have your weak areas covered, you will show with confidence because you have nothing to fear.
No matter how bad it gets, never show any weakness in your facial expression or in your body language. If you can’t get the arena floor to open up so you can drop out of sight, then act like nothing ever happened. You may not win or place this time, but you’ve practiced mental and physical control for another show when an error might be small and you need to help your horse.

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