How do I turn on/off the headlights in the Opel Astra?

The headlight switch is on the turn signal lever on the left side of the steering wheel, as shown in the photo below.

1. To turn on/off the headlights, twist the knob up or down. 
2. To activate the high beam, pull the turn signal lever towards you for a quick flash. To keep the high beam on, push it away from you.