That pasty poo gets dry and hard pretty quickly, and can be really difficult to clean off with a paper towel and be careful not to pull it off, you can tear that delicate skin. What I've found works best, if you are in the house where it's warm, is to put warm water in a bowl and hold them in the warm water while gently cleaning the poo away with your fingers. They may struggle a little at first, but relax pretty quickly, almost seem to like it. Then put them under the heat lamp. You don't usually have to do this for very long, they grow out of this within a few days in my experience.