This article is sponsored by Home Depot:

Time is money, the old adage goes, but so is a well-winterized house. Stopping air leakages can take as much as 30 percent off your heating bill, according to the U.S. Department of Energy.

The first step is to do an energy audit of your house, keeping an eye out for the trouble spots. Windows and doors are obvious places to check, but also look at things like wall outlets and switches, plumbing vents and the attic hatch for leakage. Swaying curtains and light under your doors are sure signs, but you can find less obvious air leaks by using an infrared thermometer to check for temperature variations. Or use a lighted candle (carefully). If the flame moves, air is coming in.

Seal the outside of windows with a good quality silicone caulk; use rope caulk on the inside (it can be removed in the spring). Or cover windows with a transparent film, using a hair dryer for adhesion. Other air leaks can be sealed with caulk or self-adhesive weather stripping.  

Installing insulation yourself is not easy, but if you have an older home, chances are you need to add more. If the insulation is level with or below the floor joists, you should add more, according to Energy Star, a joint program of the Environmental Protection Agency and the Department of Energy.  

For more energy-saving tips, check out the video above sponsored by Home Depot.