How do you remove the headlight switch knob?

Should be same as beetles and kombis - screw anticlockwise.

Danny, Old Dubber is correct the knob is threaded onto the switch shaft and to remove it you simply turn anti clockwise ( the opposite way to the direction that Micky's hands go ) and it will come undone. If it has been screwed really tight you may have to hold the shaft with a pair of pliers.