I keep my show box supplies very simple:
Besides brushes (stiff and soft), tail comb/brush, hoof pick
Shampoo
Conditioner
Show Sheen
Vet wrap to wrap the tail after washing
Fly spray - and lots of it
Mosquito spray - for me and sometimes this is all that will work for gnats on the horses
Hoof black or clear
Hoof polish enhancer
Dark chalk or make-up creme for eyes, muzzle if necessary
White chalk if has white legs
Baby oil gel for muzzles & over the eyes
Hair gel (to keep down those stray wisps in the mane)
Cowboy Magic (for those last minute clean ups)
Coat shining product such as Pepi
Razors & shave creme (I do not shave my horses--I use a 50 blade on the muzzle and over the eyes--but I do use a razor to get the stubble off the lips)
Baby Wipes
Paper towels
Extra clipper blades
Clippers
Blade wash
Old terry cloth towels
And a MUST is a First Aid Kit
*Vet Wrap - at least 2 rolls
*Antiseptic ointment
*Mineral Oil & 60 CC syringe for drenching
*Eye ointment
*Scissors
*syringes & pain killer such as banamine
*Band Aids