It's very easy to add your own domain. You must have your own domain first. The actual domain name can be registered somewhere on the Internet (ICANN-Accredited Registrars list). After that, you need to add the MX record to the DNS domain settings as shown in the box below.If you did everything right then you will be able to receive new mail in page:
https://mail-temp.com/my.examle.comIf you have a domain but you are not able to configure it, you can give us access to the administrative panel or server and we will configure this domain for you. To do this, send us an email to feedback.