Summarize the following:
You should have a professional check to see that your furnace is working properly. Replace the furnace filter monthly and verify that nothing is obstructing an outdoor heat pump. Verify that your furnace is not on “emergency heat”. This will turn off energy-efficient settings and could double heating costs. Fireplaces can be a good way to heat your home, but an open chimney also exposes you to the elements. Be sure to have a fireplace door that you can close. In extreme cold weather, starting a fire can be counterproductive, because it will also allow this cold air in. If possible, you should have a professional visit your house to see if you have any insulation problems. Check for leaks in your weather stripping around your doors, windows, holes around pipes and the circumference of your garage floor. Use caulk to close up any holes.  On sunny days open your drapes to allow heat in. Be sure that heating outlets are free from obstructions. Move furniture and drapery away from the vent. Clean the vent regularly to establish proper airflow. Know what to leave alone. An insulated garage, porch, and attic are usually not worth the money that it would take to heat them. Close heat registers to save the expense of warming these spaces. Every degree that you lower your thermostat you are likely to see a 3% decrease in your energy bill. There are many things you can do do embrace cooler temperatures. Among them are:  Turning the thermostat down to 5 to 10 °C (41 to 50 °F) when you leave the house to see substantial savings. Wearing warm clothes when home. Eating hot, spicy food and drinking hot beverages. Exercising. Engaging in stressful activities.  Note that stress isn't always bad, such as an exciting video game. Better yet, combine exercise with stress, by playing active indoor games, like air hockey or Dance Dance Revolution (home version).[1] Evaporating water can cool the house dramatically. The walls and roof can hold heat from sunlight, then release it, inside the house, many hours later. Don't forget the roof!  Avoid this practice during a drought.

Summary:
Check your furnace. Close the fireplace. Insulate your home. Learn to love the cold. Hose down the house on sunny days.