This article will go over creating a Subdomain under your cPanel account.
Step 1 : Log into cPanel on the account to add the subdomain on.
Step 2 : Click "Domains" under the "Domains" section.
Step 3 : Click the "Create A New Domain" button.
Step 4 : Enter the subdomain name to add in the "Domain" text box.
Step 5 : Deselect the "Share document root (/home/username/public_html) with “domain.tld”." option.
Step 6 : Enter the directory where you want the files for this subdomain to exist.
Step 7 : Click the "Submit" button.