wiring toggle switch for Windows?

[1991 e30 bmw 318is]

Removed my console and am installing 3 way toggle switch in dash for windows. Is there one power that goes to one wire for up and another for down?.. i tryed to use multimeter on the switch but just keep getting confused with it...

[StereoInstaller1]

Use a DPDT momentary switch.

[1991 e30 bmw 318is]

Use a DPDT momentary switch.

Thats what i bought but dont understand how to wire it.

[vpilarrt]

The green/grey wire is the +12V feed for both windows
For left window:
with violet connected to +12V (green/grey wire) and black connected to ground the window goes 1 direction
with violet connected to ground and black connected to +12V (green/grey wire) the window goes the other direction
For right window:
with violet/grey connected to +12V (green/grey wire) and black/grey connected to ground the window goes 1 direction
with violet/grey connected to ground and black/grey connected to +12V (green/grey wire) the window goes the other direction

This is a 15 amp circuit so use appropriately sized switches.

[1991 e30 bmw 318is]

The green/grey wire is the +12V feed for both windows
For left window:
with violet connected to +12V (green/grey wire) and black connected to ground the window goes 1 direction
with violet connected to ground and black connected to +12V (green/grey wire) the window goes the other direction
For right window:
with violet/grey connected to +12V (green/grey wire) and black/grey connected to ground the window goes 1 direction
with violet/grey connected to ground and black/grey connected to +12V (green/grey wire) the window goes the other direction

This is a 15 amp circuit so use appropriately sized switches.

thanks, it all made sense works great.