Press and hold the POWER button for about 2 seconds.

Make sure that the indicator (blue) flashes after you release the button.

If the BLUETOOTH device was connected with the headset the last time, an HFP/HSP connection is made when you turn on the headset.

While the headset is on, you can make an A2DP connection (music playback) by pressing the button.

Check the connecting status on the BLUETOOTH device. If not connected, proceed to step 2.

For details, refer to the manual supplied with your BLUETOOTH device.