This guide will lead you on how to wire your Pico Switch as a 3-way switch to your existing gang-box and lighting. This guide is an expansion of the Pico Switch user guide.
3-way wiring diagrams.
Wiring may be easier depending on what wiring is already available in each of the gang boxes. In some installations, you may need to pull new wires to achieve 3-way control.
3-Way Switching with L/N/Load in the same gangbox: 
3-Way Switching with L/N and Load in separate gang boxes:
