I meant to write quite not quit in the post
Don't react to her when she spooks. Be quit and act like there is nothing there and don't jump when she jumps. she is watching you, waiting for your guidance. Don't give a reason for her to be scared, if you are anticipating her spooking you will tense up and she will notice. Don't look at items that scare her. Keep her moving and don't punish - that will only give her more of a reason to spook-. I practice no reaction because its the best method for rescue horses...it helps them to trust and relax..knowing your their leader and nothing will happen in your care. You can help her with spooking by not reacting at all (not even pulling the reins or lead rope, not making noises of any kind. Even trying to calm her down with petting is not good because it makes them worry more. no reaction, patience, and after a few times walking by that scary object without reacting, you will see less spook but you need to stick you your guns and not react to her reaction.
We put pool noodles in the fence and tin cans like wind chimes. This way anytime the wind blows or they walk by and these thing makes a noise it desensitizes my boys from weird noises!
show her that things she is afraid of my horse used to be afraid of her boots but i showed her that they arent going to hurt her now she is not afraid also there is a thing called a spook test you can look it up or go to this link https://www.youtube.com/watch?v=Djhlz90JzfY
My horse used to spook at birds, so I left her in the arena where the birds are, and she got used to them after being in the arena overnight. I had a friend whose horse spooked at weasel balls, she put them in her horses stall and she never batted an eye at one again.
Do some desensitization. When she spooks, let her look at the object and wait for her to relax. It's also important to be really confident so that she feeds off of your confidence and realizes that there's nothing to be afraid of :)
Keep her mind engaged. Constantly change directions, execute circles and figure eights, anything so she doesn't have time to look at anything. Talk to her and keep changing your tone of voice. If you feel her tensing up or looking, throw a leg on her and make a circle.