Headlight: Turn knob to 'ON', press button on top of switch body (behind dash), and pull out. Bezel will then unscrew.
Ignition: Turn key to ACC, insert a pin into the small hole and then turn anticlockwise (I think) to unscrew. The bezel is a bayonet fit into the switch, whcih you can push toward the dash and turn to dismantle.
Wipers: WSM says 'remove knob'. Helpful that.