Follow these simple steps to create a custom ringtone for your iPhone, using iTunes 10.

- Open iTunes 10
- Browse to the song from which you’d like to make a custom ringtone.
- Right click on the song, choose “Get Info->Options”
- In the Options tab, set ‘Start time’ and ‘End time’ for the clip you would like as the ring tone.
- Right click on the song and choose “Create AAC version”.
- iTunes will create an AAC version of the clip you’ve selected, with the same name as the original.
- Edit the original song file, back to old Start & End times.
- Right click on the newly created clip, and select ‘Show in Finder’, to open the music folder.
- You’ll notice that the clip has an extension of .m4a. Rename the extension to .m4r.
- Copy the .m4r file to your Desktop.
- Go back to iTunes, and delete the clip from iTunes.
- Drag and drop the .m4r file from your Desktop to iTunes Ringtones folder.
- Sync the ringtones with your iPhone.

That’s it! You’ll find your custom ringtone in iPhone (Settings->Sound->Ringtone)

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