First of all, on the skirt, you can see that the concave and convex surfaces are sprayed with particle glue. Before repair, the scraped concave part is pulled out with a sheet metal machine, that is, lacing and shaping.

This technique must be delicate, and fine-tuning is the key. Then use a rubber hammer to knock from the outside to the inside to repair the overall modeling work. Finally, fine-tune it with a pencil tip to highlight the convex marks of the car body.