What is the reason you're scared to take a shower. I think you need to first realize this, then rationalize your fear, weigh the ups and downs of whatever it is you're scared of and then think of the probability of it actually happening. For example. I used to have a small fear whenever there was a storm to take a shower. I thought the electric may go out and I wouldn't be able to see then slip and fall and hurt myself. But after weighing the chance of that actually happening, I conquered it. So I would do just that.