Remember,

there are four basic designs in Power Window Circuits:

-Negative Pulse
-Positive Pulse (with and without Relays)
-Voltage Reversal Rest at Ground
-Variable Voltage

I would first find your Relay(s) (if there are any) and trace out the wiring-what powers the Coils? What triggers the Coils? Does the Relay have an 87a Terminal? Is it bridged? And so on-