Paper towels, the brand that says you only need half the # of paper towels. Or, (I kind of already did this one) Sharpie. They say it's "permanant" but, I wrote on my arm with all the colors in the rainbow in Sharpie (for the Day Of Silence), and the next day it came off but, not with water, with sweat. I had my watch on over where the Sharpie was and I sweated it off! Idk how or why but... yeah.