You need to get yourself vagcom. That way you can find out why its come on and once fixed you can clear the fault code.
Its most likely the connector under one of the seats for the side airbag.
Genuine Vagcom is around £200-250ish, however if thats too much you can buy a basic lead from ebay for about a tenner, which you can use with the trial version of the software and do the basics, such as reading and clearing codes.