I share a shower between 9 of us (it sounds gross, i know, but it gets cleaned every day so it's fine :P ) and I wear a dressing gown and plastic sandals to the shower. I carry my towel in a plastic bag and carry 2 huge bottles of shampoo and conditioner. I have my room key around my neck on a lanyard.
It's a pain. But would it be worth paying £35 more per week to have my own shower? i think not...