To use your creation as a ringtone, on the iPhone tap Settings > Sounds > Ringtone. You'll find it at the top of the list of ringtones. Tap it, and it will be the sound your phone plays when a call comes in. Of course you needn't use it only for ringtones: On the iPhone you can choose it as an alert sound as well.
And that's it. You, the person who claims to lack any skill for making music, have found a practical use for GarageBand. You've additionally learned something about creating and editing tracks. We'll use those skills in our next lesson when you create a musical work based entirely on GarageBand's bundled loops.
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