Create a template material called Simple_Diffuse_Only :

A "simple" diffuse shouldn't mean a "flat" diffuse. A single solid hex code often looks plastic and fake. To make a simple diffuse texture pop, you need subtle color shifts. Pick your primary mid-tone color.

To "prepare a piece" using the SimpleDiffuse generator in Substance Painter, you can follow this streamlined workflow to create high-quality, stylized textures in under 10 minutes.