QUICK INFO:

• This operation presupposes that you already have a backup copy of your Tails with the Persistent Storage, and that  (having worked on the first copy) you want to keep the backup copy up to  date.

• ​Plug  into the computer the USB stick with the backup copy of Tails >  "Places" > click on the USB stick > insert the password of the  Persistent volume to unlock it > "Applications" > "System Tools"  > "Backup Persistent Storage"