Make sure you don't lose the heat you generate. Update the weatherstripping on your doors and windows. Use draft guards at the bottoms of doors (purchase them or make your own).

Dress warmer in the house. Don't expect your heater to keep the house at 76 degrees when it's only 20 degrees outside. Add a layer or two to your clothing. A down or knitted vest will keep your trunk much warmer, which will keep your arms and legs warmer.

Wear a hat! You circulate enormous amounts of energy through your head, and you lose 65 percent or more of your body heat through your scalp. Wearing a knit cap or scarf on your head can keep the rest of you a lot warmer.

Make use of natural insulators. Down comforters and featherbeds, or fleece sheets and mattress pads, can make a big difference for sleeping warm. If you don't want to use animal materials, there are synthetics available in every category that do just as good a job.