There are two ways to unlock this, the first is to play the game every day of the week OR the second way is to change your consoles date, you can do this by the following:
-Go to Settings
-Date and Time
-Set date and change the date by one each time.
You can now load up the game up and once you are in the pod exit and change the date again, once you load up on the 7th day in a row the trophy will unlock.