Single Switch 6 wires?

Mikemonica

I just purchased a house built in 1978, I noticed the garage light was on constantly, when I went to turn off the light there was no light switch. In the garage where the switch should be, there is a switch plate cover. I removed the cover and found 3 black wires connected together with a wire nut and 3 white wires connected together with a wire nut. Why are their 6 different wires and how do I wire a single switch to be able to turn off the garage light? Many thanks for any assistance!

plummen

id figure out which black wire goes only to garage light and seperate it from other 2 wires.
then i would pigtail the other 2 blacks with another piece of wire and hook it to one side of a light switch,then hook black wire from light to other side of switch

Mikemonica

All 3 black wires to the switch? Do nothing with the 3 white wires?

plummen

yes the white wires are neutral wires,tuck them back into box out of the way of switch