Please note that it is very important to fill in your ESN card! When you buy one, fill in the information and add a photo. Without a photo, your ESN card is NOT VALID! Just print out your Facebook profile pic, and you’re good to go...
Here is an example of a filled in ESN Card:
Higher education institution: The university you study at. Most likely this will be University of Southampton
ESN Section: ESN Southampton
Country: country where you’re doing your Erasmus (UK)
Valid since: the date on which you bought your ESN card