Paint Brush

Description
Use to paint building blocks. You can also erase unwanted paint from blocks with the primary action. Requires Paint. (item not available on console yet)

Usage
While holding the  hold (R) to bring up the radial menu, select Materials the very first option. As of 19.5 there is 177 patterns you can paint blocks.

After you select your Material, Right Click to paint the surface or Left Click to erase.

Pinsel