Login to your NetworkSolutions.com account
Login to your NetworkSolutions.com account located at http://www.networksolutions.com
Under the "Domains Names" menu go to "Manage Domains"
From the Left hand side menu select "Manage Host Server".
Insert the primary name server information. Enter the name server name as you want to use it in the first dialog box and click "Continue".
Enter the primary name server IP address and click "continue".
You can get the name server IP addresses by contacting support.
Confirm the changes to be applied and click "Apply Change"
If the process was successful you will see this notice:
You need to repeat this process for your secondary name server. Once that is done, you will need to wait for DNS propagation to occur before being able to use the newly created name servers.
Once they are propagated you will need to set these name servers in the control panel.