Login to your CPanel
Go to Email Accounts
Click Create
Insert your USER NAME ONLY, PASSWORD and check the unlimited option then, click create as shown in the picture below.
To create a forwarder email to your primary email account, click Forwarders
Click Add Forwarder
Insert the forwarder USER NAME only then, choose your domain name.
Then, insert the email address that you want to receive the forwarded email on. Then, Click Add Forwarder
Follow the steps as shown in the picture below:
