The apple watch device needs to be connected to a Bluetooth audio device to play music. The method is:

1. First, click the settings icon on the apple watch interface to enter the apple watch settings page.

2. In the settings page, find the Bluetooth setting item and enter the detailed settings page.

3. After entering the Bluetooth settings page, turn on the nearby Bluetooth audio devices, and then the apple watch will start to search for nearby Bluetooth audio devices.

4. After a moment, the apple watch can successfully connect to the Bluetooth audio playback device.

5. Now return to the home page of apple watch and click the music icon to enter the music player.

6. Select the music you want to play in the software, and you can listen to the selected songs on the Bluetooth audio device.