Plugging in the Hardware
Now that you've collected your current settings, you are ready to rock and roll, er, plug and unplug things.
The first thing to do is to power down the computers on your network, any hubs, switches, or routers, and your cable or DSL modem. You may have to unplug the modem to turn it off because many of these devices don't come with power switches.
If an Ethernet cable is plugged into the back of the modem, unplug it.
Remember that with the AirPort Extreme Base Station, you need an Apple computer that is both connected to the Internet and has an AirPort Extreme card before plugging in the AirPort Extreme Base Station. ...