Cannot connect to terminal with putty

Hi there,

I'm having trouble connecting the linux terminal using the RS232 cable. I basically don't know how to do it

So I downloaded putty

Next find my galileo's IP address. So I connected to my Wifi and then used the system("ifconfig &> /dev/ttyGS0"); command to get it. It is 192.168.0.100

Then I opened putty, inserted my IP and changed the baud to 115200.

But it will not connect for some reason. I get a "network error: connection timed out" error.  What should I see on the screen? Do I need to power on/off the board?

Thanks

Tom