USB cabling for the 1ch Gateway is really simple:
If all goes well, and you have more than one gateway connected you can use color coding to distinguish between cables and gateways etc.
Once the Single Channel Gateway is operational, it works over WiFi with a GUI browser on its internet address, and connects to the server over MQTT. For local monitoring, but it can also connect to a Serial port of your computer.
Most people will use the WiFi option as it provides almost the same functionality as its USB counterpart. Only monitoring it is not real-time as it connects over a browser.