How can I make a song my ringtone on iPhone without iTunes?

How can I make a song my ringtone on iPhone without iTunes?

If you already own the music, you can easily create your own ringtones for your iPhone with GarageBand. The process is straightforward, just send your ringtone directly to iTunes. Once your ringtone is in iTunes music library, simply sync your iPhone, then go to Settings > Sounds on your device to set your new tone.