I helped one that my broody left and it hadn't pipped very far at all. But because it was cold I decided to help. I had in a wet rag while I took the shell off but I didn't wrap it after that, I just put it in my incubator, which warms up really quickly, thank goodness. It was really weak, and had a yolk sac of sorts, but after a few hours it was dry and I helped it drink some water and gave it back to mom. For the next few days I made sure that I got some food and water, but now after two weeks I can't tell which one it is. I guess mama hen had decided that 8 babies was enough, fooled her.
I think that they usually wrap them in a moist towel if they aren't fully ready to hatch. Good luck with you little one.