Please be aware that Lyyti is developed constantly and your view might not match 100% with the view described in this article.
The video below will show you how to activate and customise the calendar note in Next Gen.
When your participants confirm their registration to your event, they get an option to save the event in their calendar.
The option to save the event will be displayed on the thank-you page at the end of the registration.
To activate the option, go to Your event / Settings / Advanced. On the same page, you'll be able to customise the text of the calendar note with personalisation texts and links.