Using the GarageBand app is very simple. The first step is to load the song onto your iPhone. Once you have downloaded the song, it will appear in the music list on the iPhone. If you want to edit the ringtone, you need to drag it into the second track of the GarageBand editor. If you're using the iPhone, you'll see that these tracks are not keyboard tracks. Instead, you'll be using yellow sliders and waveforms to set the start and end points. You can pinch to zoom in and out to get a better view of your waveform.