4. Upgrade your thermostat
Look into getting a smart thermostat, if you don’t already have one. Smart thermostats let you control your heating from your phone, which means you don’t need to be at home to switch it on or off. That way, if you forget to turn it off before you leave your house, or if you’re running late, you can ensure you’re not wasting energy warming an empty home.
Source: Energy Saving Trust