Horses understand tone of voice, not necessarily the words you use. When asking for a transition, ask in higher pitched voice. Separate the words by emphasizing on syllables. For example, pronounce canter as two words, can-ter. This distinguishes between trot (one word). When transitioning down, go to a lowered voice and drag out the word. When asking for a halt, ask in lowered drawn out voice and discontinue eye contact. If the horse is truly paying attention and acting under submission, the horse will eventually come to a halt after losing eye contact. When asking to speed up but merely stay in the same gait, I kiss or cluck - no voice commands, this is confusing. If the horse is ignoring all my request and simply keeps rushing forward, I cut them off with the whip, make them stop and then allow them to proceed. If they ignore me, I cut them off again. They soon pay attention. If they are exceptionally energetic and ignoring my commands, I send them forward forward forward. Soon they will appreciate my request to transition down rather then run through them. Practice these commands, it takes time. Remember consistency. If you ask for a canter and they break to a trot without you asking, command cantering again and allow them to trot on your terms.