Installing a dimmer in place of a regular light switch is very simple. The one wire that the dimmer has that you will not find in the light switch is a green wire that is meant to go to "ground". You simply secure this wire under the head of one of the large grounding screws that are in the bottom of the electrical box. Straighten out the rigid copper wires and cut them about half an inch long. Wrap the flexible wires from the dimmer switch around the copper wire and secure the wire cap over the two to hold them together. (It doesn't matter which wire from the dimmer is connected to which wire from the old switch.) The hardest part is rolling the wires back into the box tight enough to leave room for the much larger dimmer switch.
My real tip for this work: wrap a piece of duct tape backwards around your wrist, glue side out. This bracelet will hold onto all the small screws while you are working.
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