Lunge line, side reins, standing wraps, first aid box, braiding supplies, lineament, 2 white pads (one for each day) I have a pair of breeches for each day too, but I'm a slob. I usually have a denim skirt that I put over my breeches to try to keep me clean.

chair, fan for horse, fan for tack stall, extra wipe towels (for you, tack, horse, these are very important), show sheen fly spray, test book. Don't forget your test book!

Cooler, snacks, horse treats, sugar cubes (help with salivation) I always carry horse electrolytes and orange flavored crush or orange flavored packet of gatoraide to put in horse water in case your horse doesn't drink. Orange seems to work well.

double ended snaps, extra leadrope, stall guard if you have one. It keeps the horse in the stall even with you running in and out tacking and grooming. muck fork and bucket, enough buckets to have two in the stall for water. (those are probably in the trailer, but may need to be cleaned)

I always have a "jar'o bungees" as I find them and a couple of wads of baling twine or wire to be very helpful for so many things, from putting up the buckets to used as a clothing rod in the tack stall. I also have a sleazy for the braided necks, and some Oxy Clean powder. If you get a bad spot on your pad, breeches or horse, you can make a paste, leave it on for a couple of hours and then brush it off when dry, and the ick will be gone too!

You probably don't have this problem yet, but now I have to remember to put in my reading glasses as I always end up reading for a half a dozen or more people. The 'human megaphone' no longer has 20/20 vision, and some of those test books are printed 'way too small!!!

OH, I ALMOST FORGOT! the most important thing of all. DUCT TAPE! good for wrapping a foot after a lost shoe and also for holding those boots that popped their zipper!