When you’re home, lower your thermostat to 68 degrees or less. When away, consider a setting of no more than 64 degrees. Unless you’re fond of running around your house in a tank top and shorts, you generally don’t need it to be much warmer. Consider slippers and a sweater before jacking up your heat. Here’s a basic, but interesting, infographic on saving energy (and costs) with home heating.
If you don’t have a programmable thermostat, take a few minutes today to research them. If you subscribe to consumer reports, check out their comparison of favorites. Lifehacker also has a list, though theirs are largely wifi based.