In the TCP/IP configuration, set a static IP that is unique for each machine in the last octet (ex. 10.1.0.x) and make sure the subnet mask matches (255.0.0.0 for this example). This will work if you don't need an internet connection otherwise you will have to leave them all set to DHCP for simplicity and just plug one of the ports into the LAN port of the router connected to the internet.