If you need to configure a wireless connection to your board but don’t want to wire it to your router (because you are lazy like me), you can connect it directly to your computer with an Ethernet cable  and SSH it:

Connect the board to your computer with an Ethernet cable

Open the terminal and execute
nm-connection-editor

Go to the Wire Connection Settings > IPv4 Settings
change Method to “Shared to other computers”, and save it

Now open the terminal and run
cat /var/lib/misc/dnsmasq.leases

You will get the board IP there:

With this IP you can SSH the board and configure the wireless connection, in my case using tools like nmtui or armbian-config