Join Date: Jul 2015
Location: Western Massachusetts
I have been in your shoes, when I felt too ignorant to stop some authoritative person from doing something awful to my animal. I feel bad for a long time when that happens, because I gave my responsibility away and my animal, who is mine to protect, suffered for it. When you are learning, it just happens sometimes.
Bridling is very easy on a well-broke horse like yours. If you are moving slow I can't imagine hurting a horse's teeth, and slow is the only way you should be moving. It is a gentle procedure.
It's a simple but coordinated movement in which your right hand holds the top of the headstall, from between the horse's ears, while your left hand offers the bit by placing it gently against the teeth right where he is going to open his mouth. A trained horse will lower his head when you put a little pressure on his poll, and will open his mouth for the bit when he feels the bit against his teeth.
Important: if you want to learn how to do something, don't ask someone to demonstrate, ask someone to tell you how, step by step, as YOU do it. A lot of this stuff is just learning a physical routine.