1. Insulate! Many homes, especially old ones, have lots of little cracks all over the place. I know in my house, the freezing wind can seep through spaces between the door and the wall and the windows. You can purchase a "door snake" to stuff in front of the crack, or put in a "door sweep" underneath the door to minimize the extra space. Other ways to easily insulate include drawing curtains over windows and not leaving doors open for too long.
2. Install a programmable thermostat. The article "Keeping Warm for Less" from This Old House recommends using this thermostat to set temperatures for different times of the day. This saves money because you can lower temps when you are not home or when you are sleeping. This can save 10-20% of your heating bill. According to the article, these are the settings you can use:
6 a.m. to 9 a.m. = 68 degreesObviously, adjust to your own preferences. If you have a nice, cozy bed with a big warm comforter, maybe you can deal with a temperature lower than 60 degrees at night. You can then preset the thermostat to start warming up an hour or so before you wake so you can get up to a toasty house.
9 a.m. to 5:30 p.m. = 60 degrees
5:30 to 11 p.m. = 68 degrees
11 p.m. to 6 a.m. = 60 degrees
So, that's it for Part Uno! Second installation to come shortly. Image is from caaneo.ca.