1️⃣ Standalone Unity
Before anything else, make sure your color space is set to linear:

Installing LTCGI
For standalone Unity, you can import LTCGI as a git package with the URL: https://github.com/PiMaker/ltcgi.git
⚠️ If you are importing LTCGI into an existing project, make sure you have a backup first!
The package currently declares Unity 2022.3 support. Standalone projects do not need the VRChat SDK or UdonSharp; the runtime adapter will compile as a normal Unity MonoBehaviour.
If you are writing shader includes manually, use the package path:
#include "Packages/at.pimaker.ltcgi/Shaders/LTCGI.cginc"