A method of producing a prefabricated roadway marking strip material adapted to be applied on and secured to selected areas of a prepared roadway pavement so as to form thereon a traffic regulating indicium comprised of defined signalling surfaces having nighttime visibility and non-skid properties consistent with that of the adjacent roadway pavement. The material comprises a base layer and a traffic-regulating, sign-forming and traffic wear-resisting upper layer having a generally smooth surface, spaced protuberances bulging from said surface and reflective elements concentrated on the top portions of the protuberances for providing said visibility and non-skid properties.