Log in to your co.cc account and select the "Name Server" link on the left hand side
Name Server 1: ns1.redfoxhosting.com
Name Server 2: ns2.redfoxhosting.com
And click Set Up
Remember, this will only work after Frank has created web space for you.
If you do this and there's no webspace created then you'll get the hosting company's default error page so ....
ASK FRANK TO CREATE YOUR WEBSPACE BEFORE YOU DO THIS.
Existing users can update DNS name servers if they want but it's not essential.