I have a strobe light that I want to control with a foot switch.

How would I connect this?

120v
Black, green and white wires in the strobe light.

The black is your hot wire, white is neutral and the green is a ground. Your switch will be attached to the black wire interrupting the flow of power to the strobe. You should also have the green wire connected to whatever box and switch you chose. The white can travel through the switch box but it will not be connected to anything in the box, it goes to the strobe. The switch could be the kind used to control some shop tools. I have one that requires no wiring on my part. This switch plugs into an outlet and the tool/strobe plugs into the switch cable. Some sump pump float switches also operate in this manner. Whatever you do just make sure you foot switch is grounded.