Method:

1. Download your favorite music to your computer.

2. Drag or add music to itunes music.

3. Plug the data cable into the computer to link the iPhone with iTunes on the computer.

4. Select the music you like in iTunes and click the sync button to synchronize. In this way, the music you want on your iPhone will have the songs you want.

Download Aisi Assistant, you can change ringtones without jailbreaking, and you can also add music.