How do you  use apple airplay?
 1 Connect your computer and Apple TV or AirPort Express to the same Wi-Fi network. 2 Open iTunes. 3 Click to the right of the volume slider in iTunes. 4 You'll see this icon only when you have an AirPlay-enabled device on the same Wi-Fi network. Then an AirPlay-enabled device is available, you'll see to the right of the volume slider in iTunes. 