Watch the Create an Ending online guitar lesson by Ravi from 1-2-3 Songwriting
The ending requires the same process as the intro. At the beginning your are presenting the song and at the end you going to leave your listener the last impression. You could decide to fade, which is very common and quite effective. However, once again imagine that you are playing your song live - just you and a guitar. How are you going to get out of this? A big rock and roll ending, a subdued exit, or something deceptive where the audience doesn't actually realize the song is over and perhaps leaves them unsettled? Just make sure your storyline is consistent with the feeling. Consider your message and the feel, and get out! Then, check that off your check list.