1. Open the QQ music client or visit the QQ music webpage. Enter the name of the song you want to download in the search field, and then click the Search button. Find the song to download in the search results, and click the song name to enter the play page.

2. On the song playing page, you can see a download button, which is located below the song cover or above the player control bar. Click the button. In the pop-up download option, select standard quality, which defaults to MP3 format. You can also choose other sound quality options as needed.

3. Click OK or Download button to start downloading the selected MP3 music file. After downloading, you can find the newly downloaded MP3 songs in the local music or download folder of QQ music client.