Check your furnace's filter each month and change when dirty.
Clean area around the furnace by removing trash and anything that can catch fire; you will not only keep your family safe, but it will also improve the airflow to the furnace.
Have your furnace inspected and tuned-up by a professional once a year.
Save as much as $25 a month by turning your thermostat back 5°F.
Install an automatic thermostat that allows you to reduce the temperature after you go to bed, and have it turn back up before you wake - then down again after leaving for work.
Make sure all heating registers, air suppliers and return vents are unblocked.
Don't use your stove to heat your home. Not only is it expensive, but it doesn't heat well and is extremely dangerous.