To create your own materials, begin by appending the Sturdy Standard and Sturdy Pro materials from the provided sturdy-shader.blend file.
NOTE: For faster access, you may also copy the sturdy-shader.blend file to your Asset Browser folder. That way, no matter what Blender file you’re working on, from your Asset Browser you’ll be able to drag in the Sturdy Standard and Sturdy Pro materials, and with them their respective node groups.

Then you may choose one of the following methods:

• DUPLICATE AND REUSE THE EXISTING MATERIALS
  Make copies of the provided Sturdy materials, rename them and boom: customize each new material using the adjustment stack on the node group.
  
  
• CREATE YOUR NEW MATERIAL FROM SCRATCH
  1. Create a new material on the Shader Editor.
  2. Delete the Principled BSDF node.
  3. Use the SHIFT+A keyboard shortcut (for Add) and, from the Group option near the bottom, choose one of the Sturdy node groups.
  4. Plug the output of the Sturdy node group on the Surface slot of the Material Output node.
  5. Rename your new material and customize to your heart’s content.