Ok, well besides basics, does your horse wear polos, or boots? Forgive my ignorance, I have no idea what horses wear when jumping, if anything. All your grooming supplies, bands if you're braiding. All your clothes, and any grooming supplies. Hair bands, hair spray, ect. Friends/family to cheer for you. Cash, and extra snacks. If there are issues with bugs, then bug spray, sunscreen lotion/spray. Hmm, that's all I can think of right now. Did I help at all?