Because this is still in development there is no VCC repositoy for it yet, so for now you can find the manual download here.
https://vrchat.com/home/world/wrld_9da99c69-cbc1-49bf-8a9c-05f0fc7a329a/info
This is what the Settings look like!
If you want to try it out you can download it here. To use this in your world you just need to import it in your project and grab the prefab you want to use from the ModernUIs folder! You can also take a look at the included example scene.