1. First enter the mobile desktop and click on the Meitu Xiuxiu software.

2. In the software interface, we click the video editing button.

3. Open a video from the mobile phone, click the Start Editing button, and click the music tool in the new interface.

4. Select the music you like from the music library as the background sound, and click the use button on the right.

5. In the new interface, we set the playback timeline of the background music and adjust the volume through playback.

6. Return to the music editing interface, we set the fade-in and fade-out effects through the slider button, and then click the save button in the upper right corner of the video editing interface.