All breathing needs to be done by the nose only. Oral breathing weakens the heart. Inhalation and exhalation should be the same length, and should be kept constant throughout the practice.
There should be smooth flow, no breaks, and a low sound at the base of the neck. Long and deep breathing activates the fire of digestion that burns in the lower abdomen and helps to get rid of toxins from the body.
The poses need to be done in a methodical way, with proper alignment and proper guidance, by a Master following the parampara. One asana must be perfected before another begins. In this way, one gradually builds strength, stability and health. Too many asanas, which run too fast, weaken the body. All poses are interconnected.