Place the body in a position which is stretching the desired line
Bring the arm behind your back and grab it with the other hand covering the backside of the fingers and wrist while you slightly pull it towards the opposite side putting it into a stretch. Bend the wrist with the palm in, and let head fall towards opposite shoulder in a side bend.
While in the stretched position the aim is to create tension in these muscles, without moving out of the stretch
Press the head towards an upright position. Press the back of the fingers and wrist towards the outside while giving counterpressure with the other hand. Also activate the muscles on the outside of the shoulder by pressing the arm outwards as if trying to lift the arm in an arch out from the body
Hold the tension for 8 seconds
After the 8 seconds of tension, try to move further into the stretched position by pulling the arm further towards the opposite side, while bending both the wrist and fingers in. Also side bend the head towards opposite shoulder
Hold this position for 15 seconds. Repeat the exercise until completion. Normally this is done with a total of 3 rounds of tension and stretching