1. Open "itunes" and select "File" - "Add Files to Library" in the menu bar.

2. Select the song to be the ringtone and click "Open" ”

3. The song will appear in “Music” in “Library”. Right-click the song and select “Show Introduction”

4. Select “Options” and fill in the “Start” Time" and "Stop time" (within 40 seconds), -"OK"

5. Right-click the song again and select "Create ACC version"

6. The same file appears Files with the same name but less than 40 seconds in duration

7. Right-click the newly created song, select "Show in Windows Explorer", change the "m4a" format to "m4r", and then pop up Select "Yes" in the window

8. Check: Find "Preferences" in "Edit" in the "iTunes" menu bar, open it, and tick "Ringtones" in "Common" - "Source" , and then "OK"

9. You can see "Ringtones" in "Library". Open "Ringtones" and you can see whether your files have been converted into ringtones

10. Then open "iphone" in "Devices" and select "Ringtones", check the "Sync Ringtones" item, select "All Ringtones" or "Selected Ringtones", and then select "Sync".

11. After the "Ringtone" is successfully synchronized, the ringtone will appear in the phone's "Settings" - "Sounds" - "Ringtones" - "Customize". To use this ringtone, just select it