By default we have set noMachine to listen and use port 4000 using the NX protocol. When installing the noMachine client all default settings will work our of the box however after you successfully connect you can then configure optional settings such as setting the Quality setting to maximum and also setting the resolution to suit your desktop screen of your monitor.
If you cannot connect via noMachine check if your VPS is switched on and has booted properly. In addition connection issues also happen due to incorrect firewall settings. Upon provisioning we only allow port 22 and 4000 however you can open ports as needed using the iptables module in Kali Linux