I got this from godaddy's support desk, it may provide some general help:
To create a CNAME you will need to access the Total DNS control panel, please use the following instructions create a CNAME for your domain. To setup Total DNS Control on a domain name that is Parked or Hosted with Go Daddy (A, CNAME & MX Records):
First, log into your account:
• Go to the Go Daddy Account Login Page
• Log in using your account username (which may be the same as your customer number) and password
If you have trouble logging in, our password reset form may help you. You can find this form through the following link:
Account Retrieval Page
Once logged in, follow these steps:
• Select 'Manage Domains' from the 'Domain Names' menu at the top of the page.
• Click on the domain name that you wish to configure DNS entries for.
• Click the 'Total DNS Control And MX Records' link from the 'Total DNS Control' section.
• Create and/or edit the existing entries for your domain.
*A popup blocker may prevent the window from opening properly. 'Switch to Advanced Mode' will allow multiple record changes at once.