Turn off power at the circuit breaker
Verify the switch box power is off using a voltage tester
Remove the existing switch cover plate
Unscrew and remove the existing switch from the wall box
Label the existing wire connections (line/hot, load, neutral, ground)
Disconnect the existing switch wires
Confirm the dimmer you have supports the wiring type in your box (check for neutral wire availability)
Connect the dimmer wires according to the dimmer’s wiring diagram
Connect the green or bare copper ground wire to the grounding screw/ground wire in the box
Connect the dimmer “LINE/HOT/INPUT” wire to the incoming hot (power) conductor
Connect the dimmer “LOAD/OUTPUT” wire to the wire going to the light fixture
Connect the dimmer “NEUTRAL” wire to the neutral conductor in the box (if required by the dimmer)
If the dimmer has a ground pigtail and the box is metal, connect it to the box ground
If the dimmer uses screw terminals, tighten securely; if it uses push-in terminals, insert fully
Cap off any unused wires with wire nuts as required by the dimmer instructions
Ensure no bare copper wire is exposed beyond wire nuts/terminals
Carefully tuck wires back into the box without pinching them
Mount the dimmer to the wall box and tighten mounting screws
Install the dimmer faceplate/trim per manufacturer instructions
Restore power at the circuit breaker
Test the dimmer by turning it on and adjusting brightness
If the lights flicker, don’t turn on, or the dimmer hums, confirm bulb type/ratings and recheck wiring per the dimmer instructions