Replace a light switch

Know which switch you have before you buy one. A single-pole switch has two screws and controls a light from one place. A three-way switch works with a partner, and has a common terminal that is marked or a different color. The videos here cover each type, plus a dimmer, with the wiring explained.

Turn off the breaker for that circuit and test every wire with a non-contact voltage tester before touching it. Photograph the old wiring and label the common wire on a three-way. Older homes may have wiring that is brittle or ungrounded. If anything looks scorched or confusing, stop and read when to call a licensed pro.