Question re spider kenny's wifi blog :)

Hi there,

I'm following Spider Kenny's blog for setting up Wifi on my board through the terminal. http://www.spider-e.com/wp/?p=180

I've connected through the terminal.

About half way down the instructions it says

"Using your favourite text editor add the following lines to the interfaces file."

# Wireless interfaces

auto wlan0

iface wlan0 inet dhcp

wpa-driver wext

wpa-ssid <SSID>

wpa-proto RSN

wpa-pairwise CCMP

wpa-group CCMP

wpa-key-mgmt WPA-PSK

wpa-psk <KeyFromPreviousInstruction>

This might be a very silly question - but how do you actually do this??? Would I copy this text into a notepad file? How do I get it onto the board?

Thanks

Tom