When I first got my gelding he was extremely scared of loud
sudden noises, I used tarps, kroger bags and used a speaker to replicate thunder.
Anything that rustles or is scary in any way! Sometimes I put a coat or a hi vis jacket over a jump. You can also play sound effects through a speaker.
I bought a squeeky dog toy with rustling foil for my gelding, also things like hula hoops are really good for desensitizing them and I use them as well
Tarps, or anything they find scary, just rub all over them.
Walk over boxes and things that are scary to help for the show arena!
Balls, polls, bags, flags, umbrellas, water jumps stuff that se is scared of
We have a pool noodles hanging from our gate and get the horses to walk through them tarps too and he tie flags and plastic bags on the ends of dressage whips when we train trail horses we use a stock whip to replicate branches breaking :)
plastic bags tied around your field, we also have plastic bunting hanging around there stables, good way to desenitize to loud noises but also brightens up the yard 😃
I love tarps, plastic grocery bags, and ropes