I found useful instructions on how to do this from these two links site1 and  site2, however they didn’t fully explain every part as clearly as i would like, so here is a clear step by step guide for windows.

 

Step 1

I formatted my usb with the FAT32  format. This is done by going to my computer, and right clicking the USB you want to use and selecting format (Below left image). Then you select FAT32 from the window that pops up (below right image)

              

 

I am not 100% sure this is needed, but while i was reading through forums this did pop up a couple of times for being useful in some situations.

Step 2

You need to add the below line to Cron, by using the command: 

Then go right to the bottom of the file and add:

Step 3

You then need to open a terminal and make the media/usb directory, that is used by the USB.

 

There you go! All done. I like to use this for automatically running a file from the USB… but more on that to come.