Dents resulting from fender-benders lead many to attempt to fix dents themselves, in an effort to save the money charged by an auto bodyworks garage. The DIY approach can certainly work for those who don't want to spend the cash and have some knowledge of the required tools needed to deal with deep body dents.
Wipe away any dirt or debris on the dent in question, and drill a hole in the centre of the dent, completely through the body. Push the pulling tool into the hole and, following the directions included with the tool, forcefully pull on the handle as hard as you can in an effort to flatten out the dented metal.
Hold the handle in place as best you can (you may need assistance in doing this while you work), as you tap the dent with the hammer specifically designed for metal working. Tap around the perimeter of the dent to further even out any remaining wrinkles in the body. You may have to alternately tap the outsides of the dent, as well as approach the dent from the inside of the car.
Attach the sandpaper disc onto the end of the drill, and make even passes over the dent to remove the damaged, cracked or peeled paint from one inch outward from the dent area. Sand until the bare metal underneath the paint is exposed, and wipe away any sanding dust that results.
Fill the entire exposed area with filler putty, and allow it to dry completely. Once dry, use the fine-grit sandpaper to manually sand the dried putty patch to a smooth sheen. Spray the area with auto-grade primer and, once it has dried, sand it smooth with fine-grit sandpaper. Paint the area with auto-grade spray paint; use enough coats to completely cover the primed area and until the patch matches the car paint hue.