lol dont just stretch the neck in any direction. You'll hurt yourself.
Find a pillow that isnt too bulky and lay on on your back, with your head titled so that your eyes look out parallel to your shoulders. Turn with the neck, obviously, as you are laying flat on your back(holding up the camera may have made it difficult to tell what I was doing) Touch your chin to your body. Do both sides and hold each pose for 45-60 seconds.
Do each side five times, alternating sides.
Here is a picture so you know what I'm talking about.