How to set the dynamic ringtone of Apple mobile phone?

1, first open and start iTunes, as shown in the figure.

2. After completing the above steps, enter the interface and click File-Add File to Database.

3. Then click "Song" on the left, click the music just imported on the right, and right-click and select "Song Information".

4. Click "Options" to intercept by setting "Start" and "Stop" times.

5. Click the file just cut on the right, and click File-Convert.

6. Drag the ringtone file with the file suffix modified to the bottom of the ringtone in iTunes to set the dynamic ringtone.