1. Open the mobile QQ music client, enter the main interface of mobile QQ music playback, and click on the song list, as shown in the figure below.

2. After entering the playlist interface, click the "Add Song" function button in the middle of the interface, as shown in the figure below.

3. At this time, a menu option will appear at the bottom of the interface. Click on the third function "Edit Details", as shown in the figure below.

4. After entering the edit details interface, click the "Change" function button in the upper right corner, as shown in the figure below.

5. After clicking the "Replace" button, a menu will appear with several functional options for us to choose from. Here we take clicking the "Select from Album" button as an example, as shown in the figure.

6. Select a photo in your album as the cover of the playlist. At this time, you only need to find a picture you like in the album, then adjust the size of the photo, and finally click "OK" button, then the setting work is completed, and then you return to the playlist interface and you will find that the picture in the playlist interface has changed to the picture we just selected.