How do you ask your horse to do something?
You give them a cue.
A cue is just a signal you use to let your horse know what you want them to do. Each cue needs to be clear and distinct from other cues otherwise your horse can become confused.
You will be using both verbal and physical cues, when you are teaching your horse tricks.

A verbal cue is saying something like “back” or “touch”.
A physical cue is something the horse can see or feel. For example you may point at your horse’s hindquarters and this is the cue for him to move his hindquarters away. Or you might touch him on his shoulder and this is a cue for your horse to bow.
Physical cues work better than verbal cues
Physical cues tend to work better than verbal cues because in the horse world there are no words. Horses are used to interpreting minor changes in the body language of other horses in the herd. A physical cue can be very subtle once a horse learns to recognize it.
If you only want to teach your horse a few tricks then you might only need to use a few physical and verbal cues. However, if you want to teach your horse lots of different tricks then you really need to think about which cues you are going to use. Even though horses are very good at distinguishing between subtle body movements if your cues are too similar it will confuse your horse – especially when you first start teaching them tricks.
For example when I first taught Trigger to say Yes, I would point at the front of his head. Then I decided to teach him ‘to be ashamed’, which is where he will put his head under my arm. The cues I decided to use for this were to wave my finger in front of him while saying “Shame on you”. Trigger saw a finger in front of his face and got a bit confused and started to say Yes.
I needed to make the ‘ashamed’ cue a lot more distinct when I first started teaching it to him. I decided to put my left hand on my hip, as if I was mad with him, and really waggle my finger and whole arm back and forth in front of his face. By making my cue very obvious he then understood the difference. As he became better at the trick I could make the cues more and more subtle and now I only need to put my hand on my hip and gently waggle my finger back and forth.
You should also put some careful thought into the verbal cues you will be using when you teach your horse a trick. Don’t use words that you might say at other times.
You can even make up your own verbal cues.
It isn’t necessary to use a real word as a cue. You can even make up cue words (as long as you remember the word) or use words in a different language to keep the verbal cues distinct.
Where will you be when your horse performs the trick?
Think also about where you will be when you want your horse to perform his trick. If you want to teach your horse to bow with you in the saddle, there is no point in teaching him using a cue that requires you to be on the ground. Unless you are very flexible!
Once your horse has learned a trick really well your cues can become very subtle, but in the beginning, make them very distinct from each other. Spend a bit of time planning how you are going to teach each trick and also which cues you will use. This will make it easier to teach your horse each new trick and prevent them from becoming confused.