The only time you should be removing an airbag is when it has gone off and therefore needs replacing.
If it is still live then be very careful. Always disconnect the battery for 5 minutes before you
attempt to remove any of the airbags from the car. Do not reapply the battery power until
you are 100% sure that you have fitted it securely and plugged it all back in correctly.
Of course there are other reasons why you would be messing around with an airbag.
The main reason is that you bought a new or replacement steering wheel.
Steering wheels have a lot of issues with the steering angle sensor which can't be bought separately
so quite often a replacement wheel is sourced from elsewhere such as smart or eBay.
These wheels rarely come with an airbag attached. In fact, as it's classed as an explosive,
most couriers either won't take them or charge ridiculous fees for carrying black listed items.
The following info explains how to remove the airbag from a 450 or Roadster steering wheel.
It also covers removal of passenger airbags and seat side airbags.
There is also a handy tip so you don't get detained under the terrorism act or shot.
Steering Wheel Airbag
Fortwo 450 and Roadster 452