How to change my NS record?
CHROMEIS customers can change the NS records for your domain from:
Domain Control Panel -> Type domain name and click Search -> Manage (next to the domain name you want) -> Your Domain DNS.
Modify the NS records for your domain and then click the Update button to save the changes. It will take several hours for the DNS change to propagate.
If you are not a CHROMEIS customer, you should be able to edit your NS records from the control panel at your host/registrar. For more information on how to do this you will have to contact your host/registrar.