Cut V along the crack.

Completely remove dust with a Wire Brush, electric blower, etc., and apply a resin primer. (The photo uses Alpron W-305)

Fill the resin mortar (the photo uses Alpron HM) so that air does not enter.
* The point is to serve it about 1 mm higher than the surroundings.

Allow the required hardening time to hardening.
Once hardening , polishing with a #36 grindstone until it is flat to the surrounding area.

After cleaning, apply diluted primer or water and then apply the repair material.
It's like filling in small dents.

Once the repair material is semi-dry, use a scraper to remove any repair material.
Rub the surface with #600 paper, being careful not to leave any areas unscraped.

Apply primer diluent or water and then trowel-coating lining material .
It can be flattening evenly by applying a lining material .
Once the lining material has completely dried, use a scraper or #600 paper to smooth out any excess trowel marks and edges that border the surrounding area.
That's all for the base preparation.

Let's add color.
At first, spray a little and check the color. Let's add it little by little while drying.
There is no discomfort with the surroundings, and it is OK when the groundwork disappears.

Add a pattern.
First, smooth the surface with #600 paper.
Add stain and pattern to make it stand out from the rest.
Once the discomfort is gone, it's done.