You need to change the existing domain nameserver to point to hostrocket dns domain nameserver, so that the domain can be hosted with hostrocket hosting. To do this, login to your existing domain control panel, and go to change domain nameserver. Make sure you use these host rocket dns domain nameserver:
HostRocket DNS:
Primary Name Server: ns.hrwebservices.net
Primary Name Server IP: 216.74.71.35
Secondary Name Server: ns2.hrwebservices.net
Secondary Name Server IP: 216.74.71.36
Wait for domain propagation to complete, and once its done, your domain will be hosted with hostrocket hosting. Upload your files to hostrocket server, and your website will be running from hostrocket.
Go to Hostrocket.com