In YafaRay, we can control materials with a proper tab called Material. To be able to control materials there, we have to add a material to each object in the Blender Shading panel. Just add a material to an object, and we will override it in the YafaRay tab. In our scene, we will use four materials divided into these base colors:
Select an object and add a material to it using the Add New button.
When the material is added, change the name of the material to make it easier to find in the YafaRay tab.
Repeat the same ...