Window regulator

The switch should automatically reverse the polarity for you. If it is not doing that, then you probably need to replace the switch. You can disconnect the wires from the motor, and hook a multi-meter/voltmeter (set to 20 volts DC) and hit the switch. One way should show a positive 12 volts reading when you press the button, and the other should show a negative 12 volts reading when you press the button.

How to use a voltmeter: https://www.2carpros.com/articles/how-to-use-a-voltmeter
How to use a test light: https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester
How to test wiring: https://www.2carpros.com/articles/how-to-check-wiring

Good luck and let us know what else we can do for you.