To add an alias, perform the following steps:
Step 1 : Log in to cPanel of the account to place the domain on.
Step 2 : Click "Domains" under the "Domains" section.
Step 3 : Click the "Create A New Domain" button.
Step 4 : In the "Domain" text box, enter the domain name to add as an alias.
Step 5 : Ensure that the "Share document root (/home/username/public_html) with “domain.tld”." option is selected.
Step 6 : Click the "Submit" button.