Opel Cascada Owner's Manual page 52

50 Seats, restraints
Seat height
Lever pumping motion
up = seat higher
down = seat lower
Seat inclination
Lever pumping motion
up = front end higher
down = front end lower
Lumbar support
Adjust lumbar support using the four-
way switch to suit personal
requirements.
Moving support up and down: push
switch up or down.
Increasing and decreasing support:
push switch forwards or backwards.