Clean the surface without sanding; define and cut the progrip according to the chosen design; mask the limits in which you will then apply the glue with masking tape, then spread the contact adhesive with a spatula on both surfaces, trying to apply a film of glue as thin as possible and taking care not to have any lumps, which could compromise a good result. Wait for the glue to dry (5/10 min.) Then spread a sheet of polythene to partially cover the area on the boat with the glue, then apply the progrip without pulling it, but spreading it from the inside to the outside, gradually removing the polythene up to a complete laying, then squeeze with a roll. In case of bubbles, pierce with a pin and then press. For best results, cut off the excess part when finished.