VPS servers are different than the shared web hosting. As you have a complete dedicated space then that means you have to create your own name servers. To perform that it is very easy to do.
Step 1: You have to grab your VPS IP address which you can find it from the 'server information details' which emailed to you when you did sign up
Step 2: Go and login into the control panel of your domain provider and from there create two name servers for your domain name
example:
ns1.yourdomainname.com IP: 1.1.1.1 (VPS IP)
ns2.yourdomainname.com IP: 1.1.1.1 (VPS IP)
That's it :)
