Before I knew I had CH (when I thought I just had a curse), I used massage extensively for treatment. The massage therapist I saw at the time was pretty physiologically knowledgeable and said there's a muscle group that runs from behind your shoulder blade, up the side of your neck and across most of your face on the corresponding side and mine was tight as a drum on my right (cluster) side . He told me to lay on my back and roll a lacrosse or tennis ball under my back until it hit just between my spine and shoulder blade and lay the muscle on it then give a slow count of 30. It has helped me during clusters from time to time.
This cycle, I was reading another post on these boards that identified a muscle between your jaw and ear that is taut during an attack and to push on this muscle until it releases. I have done this a couple times for attacks and shadows; it has helped quite a bit. I have even ended an attack early using this technique. Since my busts have shown success, I've continued to use it for shadows.