If you haven't connected your player to a Bluetooth device previously you'll need to use the StreamMagic app.
Make sure your Bluetooth device is set to pairing mode (see your Bluetooth device instructions for how to do this).
Open the StreamMagic app.
Tap select output on the home page.
Select Pair new Bluetooth device.
Select your Bluetooth device from the list of available devices.
Your player should now switch its audio output to playback on your Bluetooth device.