I sprayed Static guard on the fleecy inside of my boy's winter blanket once a week, as well as sprayed a moisturizer with avocado on his coat after I rode and before I re-blanket him.
Tried the bounce sheet and it didn't work for us. I think the finer the hair, the worse it can be. Cats and rabbit type hair are bad for static. And wearing nylon or wool is also not the best, it seems to hold a charge. For us, the cold dry air was getting so bad, you could see my horse get uptight waiting for the blanket to come off. Not so bad now, but he's been shocked so many times I can't blame him. Hoping I've got the problem fixed now!