The electronic ticket will be sent to the e-mail specified during the online purchase (in message content or as an attachment).
You can print the ticket, however, it is not necessary. We encourage you to save the trees and show an electronic form of your ticket to the entrance personnel. You can do that, using your phone or tablet.
We recommend saving the ticket into the device's memory (either by saving the attachment or taking a screenshot), as the access to the internet may be limited in some venues.