I know what to do! It’s simple: lower your thermostat.
The first thing you need to do is make sure that the thermostat isn’t set too high. This can be done by either lowering the temp setting, or leaving it at a higher level and bringing it down manually later. You can also buy a programmable thermostat, which will allow you to adjust the temp as needed over time instead of just turning it on and off as needed (it takes all of 10 seconds to turn off). If you leave your house for more than an hour or two at night, this would save you hundreds upon hundreds of dollars each year in energy bills. The last thing you want is an expensive furnace running nonstop while nobody is home – that gets expensive fast!
Second, find a way to keep the heat from leaking out into other parts of your house – if possible use double-pane glass windows with weatherstripping between them, since they are less likely to leak air through holes in them than single pane glass windows are; otherwise install exterior insulation wherever possible (in attics and crawlspaces) where necessary; otherwise put up storms panels around vents so wind won’t blow air around inside walls; otherwise use thick curtains/blinds/curtains over vents when not using them. Locate any leaks if possible – but especially those located right next door neighbors who have kids that don’t