feed the switch from another light or from the main board.

wire from the switch a 3 core to your pir.

wire from the switch a twin and earth to your light, then from light to light.

in the switch (black box area) connect both live feed and live to the pir in L1 or common whatever its called.

put the return from the pir (either switch live or * or whatever) in with the outside light live on the other side of the switch.

put both neutrals in a connector block.

giving.. pir or switch operated lights.