Set up an AirPort base station on Mac
Set up an AirPort Express, AirPort Extreme, or AirPort Time Capsule to share your broadband Internet access with wireless computers on your network, and share a USB printer.
You can also set up your AirPort Express to play music from iTunes on your stereo or powered speakers using AirPlay.
Connect the appropriate cables to the base station:
Connect to the Internet: Connect an Ethernet cable from your DSL or cable modem to the Ethernet WAN port on your base station.
Share a USB printer: Connect a USB cable from a compatible USB printer to the USB port on your base station.
Use AirPlay to play music from iTunes through an AirPort Express: Connect an audio cable from your stereo to the audio minijack on your AirPort Express.
Plug your device’s power plug into an electrical outlet.
On your Mac, click the Wi-Fi status icon
in the menu bar and choose the device.AirPort Utility opens. Follow the onscreen instructions to set up your wireless device.
AirPort Express is compatible with powered speakers connected to the audio minijack. You cannot use powered USB speakers with AirPort Express.
For more information about using AirPort, open AirPort Utility, then choose Help > AirPort Utility Help.