Method for assembling a trim part to a supporting part of a vehicle

The present invention relates to a method for assembling a trim part (10) to a supporting part (12) of a vehicle, wherein the trim part (10) has an outer surface (16) and an inner surface (18) and is fixable to the supporting part (12) by fixing means (14) provided on the inner surface (18), a fixing connection being established by engaging the fixing means (14) with counter means (20) provided on the supporting part (12), the method comprising following steps of aligning the trim part (10) and the supporting part (12) such that the fixing means (14) and the cou n-ter means (20) can be engaged to each other, engaging the fixing means (14) with the counter means (20) by applying force to the outer surface (16) of trim part (10), and fastening an indicator (30) on the outer surface (16) for indicating the position of the fixing means (14).