Domain aliases are domains that you own, but which do not contain any content. Instead, they point to the contents of another domain or subdomain on your account. This is useful, for example, to hold a domain that you will later sell, or to redirect traffic to another domain.
To start, login to cPanel. Once you are in, start typing "aliases" into your search bar. Click on the aliases icon, once it pops up.
On the next page, type in the domain you wish to use as the alias and then click "add domain".
Note: Domains must be registered with a valid registrar and configured to point to your DNS servers before they can be used as an alias.