For iCloud users can setup your personal domain, I am using iCloud starting I don’t know setup lately I got how to setup personal email domain with icloud.
Let’s we go to how to setup personal email domain with iCloud,
First login to iCloud.com
Now Go to Menu and then choose Settings.
Now Setup own mail Domains, it straightly not activated yet. But this features works in iCloud.
First of all you have to make Apple need to make you domain name to work with iCloud email
Read also: Change Primary SMTP Servers in iCloud
How to Change Primary iCloud Account to Another Account
Also read: Fix Automatic iCloud Backup not Working
First of all Go to Apple Menu
Now Choose System Preferences
Go to Mail, Contacts and Calenders, now delete Secondary Account
Now Sign Out the Primary Account and go to System Preferences > iCloud.
Now Login Secondary Account.