How does someone install a Honeywell thermostat?

Disconnect all power sources to your existing thermostat. Remove the cover. Locate wire connecting thermostat and heater. Not the terminal designations. Disconnect wiring to heater. Remove old thermostat from wall. Drill holes for mounting new thermostat. Connect wires. Attach subbase of new thermostat to wall. Connect wires, matching labels. Attach thermostat to subbase.