well this is a really hard question to answer, simply because there are so many answers, you should start by specifying which discipline you are interested in, dressage? hunters? eventing? however generally what you need to wear isint that different, used in all of them (generally) are breeches, gloves, boots, chaps, and most importantly, a certified helmet. i can answer more if you just specify a little!!
He knows when you're happy, he knows when you're comfortable, he knows when you're confident,
and he always knows when you have carrots.