What are the installation steps for the Honeywell TH8320U1008 thermostat?

First, turn off power to your HVAC system at the circuit breaker. Remove the old thermostat and wall plate, then mount the new Honeywell wall plate level using provided screws. Connect labeled wires to corresponding terminals on the wall plate, push excess wire into the wall, and finally align and snap the thermostat body onto the wall plate.