If you turn the steering wheel through 90* so that one of the holes is at the top - you pop a screw driver in the hole then pull the screwdriver handle upwards.
Then you turn the steering wheel back so the other hole is at the top and do the same.
Yopu'll definitely know when the airbag has popped off.
At lot of people mention disconnecting the battery - I would until you get used to doing it, there's certainly a bit of a knack.
Try a search in google for @mk4 cruise control@ there's usually something pops up...