Linear 3way Switch help, please help me with my wiring. Diagram in post

Can someone please help me make sense of my pictures. Lets assume I currently have nothing but wires and nothing connected anywhere. The grounds are left out of the pictures. Please help me not kill myself.

In “Main”, you’ll need to figure out which of those is “line” (connected back to your breaker box) and which is “load” (connected to your light). You can do this with a wire tester / multimeter, but if you’re not sure, consult an electrician.