The ways of control of the breath are many. It must be done by realization of the self. But as long as we think that this body is our self, we cannot realize our self. And often we not only think that our body is our self, but we think that our overcoat is our self! If it is miserable we think that we are miserable; if it is very grand we think that we are very grand. It is natural to think that what is before our view is our self.