I didn't come up with this on my own--I read it somewhere but can't find it again--but the best way to wear a Narrative Clip is to use a ReadeRest eyeglasses holder. It's much more secure than the camera's clip, and more versatile too.
For best results I've found that positioning the "V" of the eyeglasses holder so it's pointing upwards works best. Also, be aware that when worn this way the camera might have a tendency to angle itself upwards. If so, try wearing it a little lower than you would if you weren't using the ReadeRest.
You can see a collection of my Narrative Clip photos on Flickr.