How to make layered materials

I saw a video tutorial about apply properties to materials with RGB masks/layers (or whaever they called) but here is the question

  • Is that mask make by hand?
  • Is there some good tutorial to make mask like UE examples props(example photo)?

The easiest way I’ve seen those masks be made is to use either a 3D paint program like ZBrush/MudBox/Substance Painter, or even the 3D painting capabilities of your 3D software (Maya, 3DSMax, etc…), you actually paint the appropriate faces of the model those colors, then export the diffuse map. Then nuke the neon paint job and paint it with your real color.