By default, the ttyS0 is assigned to the Linux console. The UART transmit and receive pins are on PB9 and PB10 espectively, which are pins 8 and 10 on the 'PI BUS' GPIO header.
Ethernet is enabled by default. Plug in the network cable will automatically connect to the Internet.
Wicd is used for manage wireless and wired interface.
Running Wicd in Desktop Environment
Open Wicd Network Manager from desktop. If the board is properly set up and connected, you should see a Window as follow.
Running Wicd in Text Mode
Open a Terminal from desktop. Type wicd-curses:
Manage network by keyboard.