To add a subdomain go to the panel, choose domains>manage domains>add new domain/subdomain.
Then just add the subdomain you want, choose php version etc and wait a bit for it to become active. All the DNS information will be set automatically unless there is something specific you need to add to it like redirecting mail server etc.
$97 DISCOUNT with [color=#CC0000]DISCOM97[/color]
No monthly setup with [color=#CC0000]DISCNOSET[/color]