Registration requires an email account.
Your email address will become your username and will be used for password reset, if needed.
It's easy to set up an email account, and once you're done you can use it for your communication needs and on other websites as well!
If you do not have an email account, there are several great—and completely free—options available for creating an email account.
™, and Outlook.com
are three that are very popular.