So I am having my first English horse show on Saturday and I am doing everything I can to get ready and of course that means shopping at the local tack stor. I had a list of things I need witch included garters. I had the person at the store help me find some in my size but I truly have no idea (a how to put them on and (b what the heck I am using them for and why. I am kind of embarrassed but could someone help.
Generally, paddock boots, jods, and garters are standard turnout for younger riders on smaller ponies. The usual age at which young riders "graduate" to tall boots is about 10-12 years of age, IME, depending on the child's length of leg, etc. Over 12 years, tall boots and breeches are more appropriate show attire.
Usually it is appropriate for older students to wear tall boots. Typically garters are only for kids younger than 12 or so. However, I would say that you should go with what your trainer says. I am sure she has a reason for telling you to get garters rather than tall boots.
I thought the rule for most hunter/jumper shows was under 14 wore the garters. In breed shows they don't really wear them much... I never wore them because I started out in Germany and there we did dressage... so tall boots all the way...