I went back and read all the post from the org. poster. Looks like he's just trying to turn on more then one light with just one switch. There's no 3 conductor wire needed to do that. If I'm wrong and that's not what he's trying to do please forgive me.
Light Switch Wiring Diagram - Multiple Lights
For some reason in this picture there showing the bare ground as a yellow wire, which in new code for 12 DC volts in boats so the 110 and 12 volt DC ground do not get crossed but the rest of the diagram is right.