Installation

• Open the project you want to include the material.
• Append the blender file you downloaded.
• Choose either the node group or the material preset already set-up, (Human, Alien Blue, Reptile Green, Dragon Red)
  
• And thats it, you should be able too see it and use it.
  

  
  

  How to use it?

  Well, just plug the node to a principled BSDF node as shown here:

  

  What does every setting do?

  Low shade: Moves up and down a sort of shade shadow in the object. Looks good specially in stilyzed type of skins. Also, the Settings of Shading Contrast and Shading Brightness control how does it look. If you doont want it you could just set low Shade to -2.
  

  

  Spots: Opacity makes the spots more visible, the size makes them bigger and smaller, but also controls the amount, the smaller the spots the more you see. The offset allows you to move the spots in the local Y axis. Basically so you can position them where you want them. Like I did with this orange spot in the eye of Suzanne.

  

  Skin Noise: It adds some color variation to the Skin. You can choose its opacity and size. Here´s and extreme example of a light blue skin with a strong orange skin noise.
  

  

  DarkS Noise: This is a subtle detail in the shader that you most of the time wont want to touch. It adds a dark noise all over the skin to add imperfection and detail. Here you can see a example of it with the value of opacity cranked up so it can be easily seen.

  

  Bump Strength and Bump Scale: This controles the scales/pores of the skin. If you make them really small they will look like pores and if you make them big they will look scales. The Strength allows you to control how visible are they. For example, in a reptile you want big and very visible scales, while in human skin you want to have tiny ones that are barely visible. You can plug the Scales preview to the Viewer node so you can see more easily what the scales look like.

                

  Subsurface scatter: Finally this setting is the one that is going to make it really good in Cycles. The default .120 shows amazing results for every skin I have tried, but not be afraid of tweaking it as you desire. The SS Brightness setting basically makes the subsurface more or less bright.