Guys this is a basic conventional wiring diagram that i represented in a simple way, to understand easily. Here Blue wire as well as Red wire is LIVE wire. But i used blue wire, to distinguish master control wire from main LIVE wire.If you want true two way master switching, you need two two way switches with strappers between the L1/L2 terminals. This method in the video requires both master switches to be off to kill the circuit.Very nice automation here i wish we did more of these curcuit types.