The procedure consists in incorporating in the actual process of conforming a roof lining, determined by the securing to each other of a previously conformed lining support and the positioning and securing thereon of a coating, of one or more electroluminescent strips which will constitute a lighting system of the roof lining, which electroluminescent strips are integrated between such lining support and coating, each of them with a ribbon cable and a connector which are made to pass through a hole of the support of the lining and is finished in a connector, which is hidden by the rear face of the actual lining for its connection to the power supply of the roof of the vehicle in which the lining is applied.