Update readme with usage instructions

README.md

@@ -5,11 +5,26 @@ Package manager for Chrome OS
 
 Overview
 --------
+
 Chromebooks with Chrome OS run a linux kernel - the only missing piece to use them as full-featured linux distro was gcc and make with their dependencies. Well, the piece isn't missing anymore. Say hello to chromebrew!
 
 Installation
 ------------
 
-Download and run installation script
+Download and run the installation script
 
     wget -q -O - https://raw.github.com/skycocker/chromebrew/master/install.sh | bash
+
+Usage
+-----
+
+    sudo cbrew <command> <package>
+
+Where available commands are:
+  
+  * search
+  * download
+  * install
+  * remove
+  
+Available packages are listed in the [packages directory](https://github.com/skycocker/chromebrew/tree/master/packages).