One excersise that helped me is to sit up with your back perfectly verticle, (make sure the lower back is straight too! Sometimes it slips and still feels like it's verticle and it's not!)
Anyways..... put your tounge on the roof of your mouth. and breathe in/out through the nose. If sitting, have your feet flat on the floor, if lying down, just make sure your back and neck are as straight as possible.
Imagine your back is a perfect pillar of light. When you inhale, breathe air in 'from your lower back' (it's hard to describe but easier done than said). When you exhale, visualize any pain as 'not light' and push it from the back and think "pain is gone, completely healed!" - with great confidence in your mind.
I hope this helps you as much as it helped me!
