When you launch the installer for LightWave you are presented with the choice of how to install. In addition to the Typical and Custom (Windows-only) choices, LightWave 2018 includes a Render Node option. This will install only the files needed to turn a computer into a render node for LightWave and runs the node in the background with no further interaction needed. The machine will then be ready to appear in the NRC list of available computers.
For completely unattended access on PC, select to configure advanced options for NRC and set to Windows Service. On Mac, select System Service.
If you choose not to use the Bonjour network discovery method for render nodes you can use IPv4 discovery. This will work automatically, but if your network requires the default port number of 29572 to be changed, this needs to be set up when installing. To do so, choose to configure advanced options for the Network Render Controller. There are several options to configure here, but if all you want is to change the port number, click Next three times to get to the following screen:
The screen after is the naming for the NRC Service Identifier.
For completely unattended installation, perhaps necessary when installing on machines not present at the install location, you can run the installer from the command line with arguments to select the various options without running the GUI. Run the installer executable from the command line with the "--help" option to see all the values that can be specified.