If your cold if your dont have a blanket use a towel, or clothes. Or take a scalding hot bath let the steam fill up the room and then dress in warm clothing and when you cant type you can like get under the blanket or what your using to say warm. If your by a heater warm up your socks put them on and sorda warm your fingers and just make it most suitable .
Get into a warm bath, and as the water cools keep adding more warm water until you're finally warmed up. Then dry and dress as quickly as you can. I did this after a snowmobiling trip gone horribly wrong (40 degrees below zero and our leader gets us lost in the wilds of the UP!) and it helped immensely.