So what do you need. Well a Z30, a memory stick and a Micro USB OTG Cable Adapter For Samsung Galaxy S4, This link brings you to the eBay item I got for a couple of pounds but you can obviously get one wherever you want..
Plug the memory stick into the cable and plug the cable into the mini USB on the Z30
The following screen will pop up
|Change the file location|
|Your USB files appear|