The following procedure shows how to setup a Wi-Fi network. Other networking methods are described in the ev3dev website.
In the menu select Wireless and Networks
Next select Wi-Fi
Power on the Wi-Fi dongle and select Start Scan
Select the network that will be used, and Connect, type the password and choose Accept. This will establish the connection and show the IP address of the device on the upper right side of the screen.
The ev3dev firmware has the ssh server enabled by default, so you can log in the brick using the following command:
Alternatively, you may use directly IP address shown on the screen
The password in either case is maker
Windows users can use PuTTY to log into the EV3 Brick.