Having just moved over here permanently, I've registered my small nursery business under my own name and received a SIRET number but hadn't chosen a 'business' name at that point. Now I've decided on a name for the nursery but don't know if I have to do anything before I advertise using this name. Can I put up a board outside the nursery with my 'new' business name and the SIRET number or do I have to start some more paperwork?