If you bring your own towel, you can wipe yourself off time and time again without disturbing the hotel's towels. This will save you from having to write notes to the staff. You won't have to put the Do Not Disturb sign on the door, so the staff can still get in to make your bed.
Since you are traveling, weight and space are of the essence. May I recommend the MSR packtowel? It's made for mountain climbing. It's super absorbent, lightweight and easily packable. These towels are also quite durable. They'll last a decent amount of time, unless you find yourself in one too many hand-to-hand combat situations.