Update README with a basic example

README.md

@@ -20,4 +20,17 @@ Make sure these executables are called the same way on your machine.
 
 ## Usage
 
-TODO
+TODO: add detailed descriptions for all parameters.
+
+Using the tool to update XDUData for the player:
+
+```
+divatool.py xdudata update [path to the 'files' folder from the game] [path to the XDUData folder for the player] [path to the 'xdutranslations' repo folder] [path to the temp files folder]
+```
+
+Example:
+```
+divatool.py xdudata update /home/user/gameapp/files /home/user/player/XDUData /home/user/git/xdutranslations /var/tmp
+```
+
+Note that the 'files' folder from the app must contain the db files for this to work.