Hello,
To use Volumio you have to access from a web browser http:// volumio.local or ipofvolumiobox from a device on the same network. From this page you should be able to set all parameters. For a more advanced use you can SSH to volumio from a term at the address pi@ipadressvolumio password raspberry (but if you don’t know what I’m talking about just use the web browser). Once all setting are done, you can use a mpd client to play your music. Volumio is not design to be used with a graphical interface directly from the raspberry.
Voila