Your Godot version:
4.0.2

Issue description:
It's supposedly possible to achieve proper skin/hair look with built-in materials and shaders. The problem is, next to no one knows how to do it. Please document.

Raised in a comment in godotengine/godot-proposals#6900 which was closed because OP deleted comments/other assets were found, so I'm opening an issue solely for the documentation part

URL to the documentation page (if already existing):
N/A