Update README.md

README.md

@@ -3,9 +3,22 @@
 ## Usage
 
 ```
-./gen.sh
+./gen.sh [profile] [target_arch]
 ```
 
+## Config
+
+- `profiles/{profile}`: 
+  - `config.sh`: (Optional) config script in chroot
+  - `packages.txt`: packages to be installed
+  - `packages.{target_arch}.txt`: (Optional) packages to be installed for a specific arch
+- `config`:
+  - `common`: common config script in chroot
+    - `common/function_enable_service.sh`: functions to be used by config scripts
+  - `{profile_set}`: config script in chroot for a specific group of profiles
+
+
+
 ## Requirement
 
 - pacman + arch-install-scripts (pacstrap + arch-chroot) (chroot support is WIP)