I saw the suggestion in a bridal gift idea roundup of a black hand/face bathroom towel and thought it was so smart. All of my bathroom towels are white. I have the Peter Thomas Roth Moor Mud Mask and the Boscia Pore Pudding Intensive Wash-Off Treatment, both black, were staining them.
I found this set of 12 for $17.99 on Amazon and it’s been perfect.
Some masks come with their towel, like this PTR set. You can also get them embroidered if you’re giving as a gift.