Have a computer connected to the router with an ethernet cable. Examples
given are for a Linksys router. Refer to your router manual or the router
mftr.'s website for default settings if you don't have a Linksys. Open a
browser such as Internet Explorer or Firefox and in the addressbar type:

http://192.168.1.1 [enter] (this is the router's default IP address, which
varies from router to router so check your manual)

This will bring you to router's login screen. The default username is left
blank and the Linksys default password is "admin" without the quotes. Enter
that information. You are now in the router's configuration utility. Your
configuration utility may differ slightly from mine.

Click on the Administration link at the top of the page. You are going to
change the router's administrative password from the default. Enter your
new password. WRITE IT DOWN SOMEWHERE YOU WILL NOT LOSE IT. Re-enter the
password to confirm it and click the Save Settings button at the bottom of
the page. The router will restart and present you with the login box again.
Leave the username blank and put in your new password to get back into the
configuration utility.

Now click on the Wireless link at the top of the page. Change the Wireless
Network Name (SSID) from the default to something you will recognize. I
suggest that my clients not use their family name as the SSID. For example,
you might wish to name your wireless network "CastleAnthrax" or the
like. ;-)

Click the Save Settings and when you get the prompt that your changes were
successful, click on the Wireless Security link which is right next to the
Basic Wireless Settings link (where you changed your SSID). If you have a
newish computer, you will be able to set the Security Mode to
WPA2-Personal. Do that and enter a passphrase. The passphrase is what you
will enter on any computers that are allowed to connect to the wireless
network. WRITE IT DOWN SOMEWHERE YOU WILL NOT LOSE IT.

At this point, your router is configured and if the computer you were using
to configure the router is normally going to connect wirelessly, disconnect
the ethernet cable and the computer's wireless feature should see your new
network. Enter the passphrase you created to join the network and start
surfing.

Additional information:

MVP Jack - http://www.ezlan.net/#wireless
Wireless - Basic Configuration - http://www.ezlan.net/Wireless_Config.html
Wireless - Basic Security -  http://www.ezlan.net/Wireless_Security.html

Malke