The present invention relates to a method to fold a sheet (11) of material into a rod for an aerosol generating article, the method comprising: providing a central element and plurality of spaced apart walls (14), the spaced apart walls radially extending outwardly from the central element (12) following one another in a circumferential direction, each spaced apart wall defining an end surface (15) separated from the end surfaces of the adjacent walls; transporting the sheet of material and putting it in contact with the end surfaces of the plurality of spaced apart walls so that the sheet of material can partly fold within spaces defined between the spaced apart walls; and inserting the sheet of material into a funnel (16) to form a rod. The present invention also relates to an apparatus (10) to fold a sheet of material into a rod for an aerosol generating article.