3. Select the user for whom you'd like to set up the email alias.
4. Click on Mailbox Settings from the left pane of the user's page and select Email Alias

5. Click Add icon and provide an Alias username and then choose the domain using which you want to create the alias.
6. Select the checkbox "Set as Mailbox Address" below the Email alias field to change the alias email address as the primary mailbox address.
7. Click Add. For more details, visit our help page.

If you want new email ID as Login Email ID
8. After setting the new email as the primary mail box. Follow this path (Security=>Login Email Address)
9. Click on the star beside the new email Id and click "change" .