Open up the zip file that's provided, copy the two files into your Asset Library folder. import any mesh to the scene and simply drag and drop the materials to your mesh from the Asset Browser

Or You can simply append the materials from the blend file to your project.

2 files are

X1 .blend file

X1 blender asset catalog file .txt

In the Asset Browser you will see two options

• Recommended method: UVMapped
  

First you need to unwrap the UVs, enter Edit Mode (provided that it does not cause significant lag), select all vertices or faces, press the “U” key, choose “Smart UV Unwrap” from the menu, and click “OK”.

If the mesh has a high polygon count, consider using a Decimate modifier to reduce the number of polygons before repeating the first step
then drag and drop a material from the Asset Browser, named CLAY##.UV

• Fast Method: AutoUV (Using blenders internal mapping method)

Drag and drop any material named CLAY##.AUTO onto the mesh. No need to Unwrap the UV's

Then you can play around with the 2 Blue Input value areas in Shader Editor

Example:

If there's any difficulties, Append the materials from the .blend file to your project.

The mesh needs to have enough polygons to see Displacement. If the mesh have low poly, you can try adding Subdivision Modifier and Enable Adaptive subdivision (Make sure Cycles Experimental Branch is enabled)