I think this is what you do:
Login to your godaddy account and edit your name servers to reflect the server change. It is usually in this format ns1.somenameserver.com & ns2.somenameserver.com
But in your case you will want to use your ip as the name servers
What you will need to do is change the 'A' Records by adding your IP address, using GoDaddy's Total DNS Control. Total DNS Control allows you to perform advanced DNS functions, such as changing your zone records.
To Manage Your DNS
1. Log in to your Account Manager.
2. Under the Domain Names section, select Manage Domains.
3. Select the domain name you want to modify using the check boxes. Your Domain Details display on the right of the page.
4. Expand the Nameservers Summary section to see what name servers you are currently using and to change them, if necessary.
5. Expand the Total DNS Control section to manage subdomains and launch Total DNS Control. Using Total DNS Control, you can modify the zone file (A records and MX records) for your domain.