Once hardened, finish the sanding with wet fine grit sandpaper for a really smooth finish and wipe away any dust. Thoroughly clean the bumper inside and out. Any dirt or grease will stop the filler bonding properly and ruin the appearance of the repair. Allow to dry and wipe down with solvent wipes, which are usually included in the kit. Remove the masking tape and sand down the damage at the front to make the area a little low and create a rough surface for bonding. Apply bonding liquid if supplied.

After any paint repair, it’s best to wax the car, preferably professionally to keep the paint in the best condition. Wait at least a week after the repair before waxing. Apply a liberal amount of repair material to the damaged area so that you make the surface a little higher than surrounding bumper. Use a spreader like a squeegee to carefully smooth out the filler. Make sure to push the filler into any scratches to fill them right to the bottom. Cover with smoothing film if supplied and allow to dry and fully harden. Sand the repair area level, first with 80 grit sandpaper and then with a fine grain sandpaper to smooth it out. If needed, apply another light layer of filler over any gaps or dips to restore the original contours.