I have a gash on my back that I can't cover...?

While cleaning one of the closets a few days ago without my shirt on, a brick fell on my upper back between my two shoulders. Luckily it only left a maybe 1 square inch gash on my upper shoulders in the middle. I immediately h2o2'd it, let it dry and applied iodine. The only problem is that I have band-aids that would only fall off. I applied medical guaze and had my wife tape that onto my back but that would only fall off by moving certain ways. This wound is on the worst place of my body to heal quickly because I can't get any kind of bandage to stay on it. Also, I'm sweating a lot as it's summer, and it burns so bad when sweat touches it. What should I do?!!!