- check out this repository, for example in your home `git clone https://code.mrflos.pw/mrflos/nixos-config.git ~/nixos-config` (ideally fork this repo and clone it with ssh to be able to commit your customs)
- copy the NixOS generated configuration to the `machines` folder `cp /etc/hardware-configuration.nix ~/nixos-config/machines/<machinename>-hardware-configuration.nix`
- copy the example configuration file in the `machines` folder `cp ~/nixos-config/machines/example-configuration.nix ~/nixos-config/machines/<machinename>-configuration.nix`
- edit your machine configuration file `~/nixos-config/machines/<machinename>-configuration.nix`, make changes and uncomment modules according to your needs for this machine