wiring celing light

Currently both the hot wire and the neutral wire connect directly to the fixture. When you have a wall switch, the hot wire goes to the switch on one wire and back from the switch on the other wire, where it is connected to the hot side of the fixture. The neutral remains connected directly to the fixture

Stay out of trouble and pay attention to your color codes: the black (hot) wire at the box connects to the new black wire to the switch and the return (white) wire from the switch connects to the fixture. Code calls for the white wire to be permanently marked black with paint, tape, whatever. You may already know this, but it's aways good to review, right?

Joe

pull a 2-wire with ground cable from the ceiling box to the switch box

existing black connects to new black with wire nut

put a ring of black tape around each end of the white wire in the new cable to designate it as "switched hot"

at switch box black goes to "line" and white with black tape goes to "load" side of switch (if switch is not marked, it doesn't matter)

in ceiling box white with black tape goes to black of light fixture

white remains as is (there is no neutral available in the switch box if you follow this method)

hope this helps

nate