24. Weather-proof your home
Buy (and use!) some weather-stripping materials and caulking, and you may save a lot of money on your heating bills. Check for drafts around door frames and windows and seal up those leaks, as they’re letting warm air out of your house or cold air in, causing your heating system to work harder than it should have to. Check for drafts around light switches, too, and know that you can add a little insulation behind the light switch plate.