Basic Apple usage

To find any software or navigation around your make click on the Finder button:-

To add more visibility of USB drives, NAS etc then go into the top menu and select:-

Finder - Preference key.

This will bring up a new screen that allows you to select what you want to see in this Finder view:-
Select Connected Server for previously assigned NAS's and External drive for USB's:-

To add a folder to the Finder list,

       Select Finder,  
           then GO on the Finder Toolbar
               Then Go to Folder

For the Linn Promotions enter /users/Shared

To add a NAS to the Connected Server,

       Select Finder,  
           then GO on the Finder Toolbar
               Then Go to Folder