disconnect battery
make a cup of tea
start with wheel straight then turn to 90 degrees
on the back you'll feel a small hole - insert a small but strong screwdriver and lever the clip off - its a little tricky but its doable
turn wheel back through 180 degrees and repeat and remove airbag
no idea on the rest from there as i refitted an R32 wheel. Would imagine you'd need some kind of resistor to fool the car into thinking the airbag is still connected