This is a test of commonsense. Complete the next sentence:

How to install a digital thermostat
Purchase a digital thermostat from a home improvement or hardware store.
Turn off the power to your furnace before beginning digital thermostat installation.
Remove the cover of the old thermostat.
Most of them simply pop off easily with a little force. Remove the screws from the screw terminals in the sub-base of the old thermostat and remove it from the wall.