Use a soft, dry and clean cloth that does not release "residues". In case of stubborn dirt, you can use a common spray for cleaning windows or possibly generic degreasing liquid. Dry the surface carefully and then apply the adhesive, taking care of its position and keeping it perfectly aligned with the shape of the vehicle to avoid "attach and detach" actions which would compromise the hold of the glue over time (handle the adhesive exclusively by the edges, avoiding touch the adhesive part with your hands). Feedback is very important to us and helps us offer a better service to buyers: We kindly ask you to contact us for any problem, we are always available to resolve any problem, before leaving negative or neutral feedback. If you don't express your satisfaction with 5 stars you can