update README

README.md

@@ -1,7 +1,17 @@
 # NavInstall
+navOS Installer
 
-## Features
+## Create install medium
-- Install different configs
+You can create a bootable install medium either with or without GUI:
-- Install with JSON file
+```sh
-- Install with CLI
+navinstall create-iso [--without_gui]
-- Install with GUI
+```
+
+## Install a system
+Install a system configuration:
+```sh
+navinstall install config.toml
+```
+
+`config.toml` is a system configuration describing how to install the system.
+Example configurations can be found [here](installs) or at `/usr/share/navinstall/installs/`.