Is there any procedure on macOS systems to manually set a network interface to a self-assigned address?
macOS self assigns an ip if the network adapter is working properly, but it can't communicate with a DHCP Server.
So you could connect your Mac to another Computer (with no DHCP Server running) with an Ethernet cable or stop the DHCP-Server on your router from running to get this effect.
Note: If you disable the DHCP Server in your router, make sure to remember the IP and subnet of the router to be able to enable it again.