1. First open the Douyin app and log in to your account. Click the plus button in the lower right corner to enter the video shooting page. Find and click the music button at the bottom to enter the music selection interface.

2. Then select the music you want to use in the music library. In the music selection interface, you can preview and edit music clips. You can drag the slider to select the starting and ending position of the music to cut the desired piece of music.

3. After adjusting the music clip, click the Finish button to return to the shooting interface, where you can perform other shooting operations, such as recording videos or taking photos. After the shooting is completed, you can make other edits to the video, such as adding special effects, filters, or text.

4. Finally, click the Next button in the lower right corner to publish the video.