docs: How to use?

[woile]

Thanks for this amazing project. I think it's exactly what I've been looking for 💪🏻

I was wondering if some documentation could be added explaining how to use it. Similar to this explanation: https://github.com/srid/nixos-config#setup

And also an explanation of what would happen next, does a user have to run nix run every time?
How to remove afterwards?

Thanks!