There is a bulge on the wall, which needs to be repaired before painting, otherwise it will affect the painted wall. The specific steps of patching are as follows:

Step 1: Clean the bulge: Clean the bulge with detergent to ensure the surface is dry.

Step 2, open the drum: tap the center of the drum with an axe or percussion tool to open the drum.

Step 3, fill the gap at the protruding part: put the caulking agent into the gap at the protruding part, and compact the caulking agent until the surface is the same height as the surrounding wall.

Step 4: Polishing: When the sealant is dry, polish the surface with sandpaper to make it flush with the surrounding walls.

Finally, in order to keep the wall flat, please check the repaired parts regularly before painting and carry out necessary maintenance.

In a word, repairing the bulge is a simple but necessary step and must be carried out before painting. If left untreated, it will lead to wall damage and uneven paint.