Clean the cracked area with soap and water
Dry the bumper completely
Remove loose paint, dirt, and debris around the crack
Sand the crack and surrounding area with coarse sandpaper
Drill small stop holes at each end of the crack if needed
Apply plastic repair adhesive or bumper repair epoxy
Press the crack together and hold it in place
Reinforce the back side with fiberglass mesh or a repair patch if accessible
Let the repair material cure fully
Sand the repaired area smooth with finer sandpaper
Apply filler if needed and sand again
Clean the area before painting
Apply primer to the repaired section
Paint the bumper to match the car
Apply clear coat if required
Let the finish dry completely before driving