Drink something hot. Use flannel sheets and a plump comforter. Sheepskin mattress pads absorb body heat in the winter and keep you cooler in the summer. Warm your bed with a hot water bottle before you get in. Put a wall thermometer next to the thermostat.
All heating systems function best when coils, filters, and heating vents are kept clean.
Portable heaters can save you money only if used to heat small areas for short periods of time. Leave shades and draperies open on sunny days and allow the sun to help heat your rooms but remember to close them at night. Close the fireplace damper when the fireplace is not in use. Light a candle in the fireplace to keep the draft from entering your home. The rising heat from the candle will not be strong enough to carry the heat out but will keep the cold from sinking.