1. Login at the Customer Control Panel with your main account’s username and password.
2. Once logged in, click on Registered Domains.
3. Select the domain you want to manage.
4. Click on the “Unset Registrar Lock” button.
5. Click on “Manage Name Servers” button.
6. Remove the existing Name Servers.
7. Type in the New Name Servers
8. Then click the “Update Name Server” button.
9. Then click the “Set Registrar Lock” button.
That's it, you've updated your name servers for your domain, it can take between 2 to 48 hours to propagate across the internet.