 usually by flipping the switch off for a second and then back on. And this allows you to keep that light on at night when you want to, even when there's no motion. So it's kind of a great option there that helps you out when no one's home and helps you out when you are. Now, if you have an existing light fixture, hooking up a new motion detector fixture is really an easy project. First step, kill the power, right? Make sure it's off.