Is a newspaper a good conductor or insulator?

Just like any other type of insulation. The point with news paper insulation is to keep a layer of air between the cold and whatever you're trying to keep warm. It's like a sweater. The idea is that your body heats the cold air in the sweater and when it's warm it acts as a buffer between you and the cold air outside the sweater. A wet suit is the same thing except you heat the water around you.