To add a drawer (directory) to your filing cabinet, choose "new directory" while on your Main FM page.
To create a sub-directory within one of those drawers, open the drawer you want to create it in and then choose "new directory".
* Wherever you are in your FM structure, that is where the new directory/sub will be created. *
You cannot move or copy a directory/sub, so make sure you create it where you want it.

In the pop-up box, type in the name for your sub-directory, and click "OK".
That's it: you've now created a new sub-directory named "pictures".
To delete a directory/sub, click on "remove" or check the box to the left of the directory/sub name and click the "delete" button.
Note: You cannot delete a directory/sub unless it is empty, so you need to delete anything it contains first.