You need a switch that is normally open, but momentarily closed when you press it with your foot.

If you are wiring for an Autopilot, it needs to be hooked in to the 2 terminal Deutch connector on the AP Harness. Sorry but my manuals are out in my shed, so I'm unable to be more specific at this time. Remember that the switch needs to be open until you are ready to engage the Autopilot. Press for a bit longer than one second, and then release, at which time the auto will engage. If you have the foot switch held down while manually turning and then release when you want to engage, nothing will happen. You need to finish manually turning, before you press and release the switch.

Did you also want to wire a switch for the EZ-Steer controller? I have the suggested cable and pinouts for that also, if you need info there.