So here we are. To adapt this Fishman diagram for toggle switches for the voices.
To adapt this diagram, you would ignore the switching part of the push-pull pots and wire the respective voice wires to toggles as follows.
Toggle switches, either of the type SPDT on-off-on or half of DPDT on-off-on could be used.
The switches in the middle give voice 1. This has to be in the middle.
Bridge pickup voice 2 orange wire to ground.
Switch up (lower terminals)
Bridge pickup voice 3 yellow wire to ground.
Switch down (upper terminals)
Neck pickup voice 2 green wire to ground.
Switch up (lower terminals)
Neck pickup voice 3 blue wire to ground.
Switch down (upper terminals)
Additionally, the black wires on the outside of the push-pull part of the pots shown in the Fishman diagram are grounds, but just shown as attached to the ground part of the switch part of the pot, ground these wires to the back of the pots instead.
Here is how the toggles are wired. A DPDT on-off-on is shown but as only half of it is used a SPDT on-off-on could be used instead if just using pots without push pulls.
This is fairly simple, in the centre position nothing is connected together via the switch. In the upper or lower position the relevant voice wire is shunted to ground which makes that voice active. Note, however, how these pickups are working internally is different to passive pickup wiring and not equivalent.
For Piezos that is separate to this, of course.