My window will not roll up. How can I tell if it is the switch, motor or regulator? 1998 Volvo s70

If your switch is bad, there will be no function up or down, nor will your hear the faint click at the motor in the door.
If the motor is bad it usually rolls down, because it takes less effort, but will struggle or die out when going up.
If the regulator is bad, it'll usually affect the gear teeth on the motor, causing the window not to hold its position resulting in the window dropping down on its own.