refactor(readme): update the readme with a nix-helper section.

README.md

@@ -1,10 +1,10 @@
 # 0x29a nixos config
 
-My personal nixos configuration files.
+My personal nixos configuration files for different environments.
 
 ## basic system installation
 
-- The installations in this repository are always luks encrypted
+- The installations presented in this repository are always luks encrypted
 - For simplicity I'm using device labels rather than uuids
 
 1. the partitioning layout should look somewhat like this after the installation
@@ -111,8 +111,24 @@ $ sudo nixos-rebuild --install-bootloader switch --flake .#host_name
 $ cd /path/to/repo
 $ sudo nix flake update
 $ sudo nixos-rebuild switch --flake .#host_name
+$ sudo nix-collect-garbage
 ```
 
+## how to use nix-helper
+
+The tool nix-helper is installed by this configuration. It simplifies administrating nixos and adds more output to the rebuild command. It also features a diff after a successful build. The command uses the `NH_FLAKE` environment variable to be able to run from whatever directory.
+
+Basic commands with a set `NH_FLAKE` variable are:
+
+```bash
+$ nh os switch
+$ nh os build
+$ nh os test
+$ nh clean all --keep 5
+```
+
+There is also the option to interface with home-manager by using `nh home switch`but this isn't necessary since home-manager is imported as a module in this config.
+
 ## author
 
 aaron <aaron@0x29a.ch>