Not too hot, just right!
There are a lot of resources around our homes that have to work harder in the colder months, like the water heater - consider lowering the maintained temperature to 120°F. Also, make sure you don't have cold air leaking into the space where the heater is, making it work harder.
When you clean the dishes from all those home-cooked meals, consider using air dry on your dishwasher between loads, instead of the hot air setting. Furnaces work hard to keep your home warm. If you're spending more time away from home, consider turning the temperature down as low as 60°F while you're gone, which is still warm enough to keep indoor pets safe.
Light the way
Don't blow a breaker – grab some LED lights this year! This year, the new breed of Christmas lights will dominate retail stores, replacing the giant, painted incandescent outdoor lights and long strings of plugged-together fire-hazard twinkle lights from past generations.
LED (short for Light Emitting Diode) lights have come a long way since first being introduced to the market. They used to be blueish in color, and looked like they were vibrating. Now, there are smoother, warm-colored LEDs and they'll likely outlive their owners, since there are no fragile heated parts, like the coil in an incandescent bulb.