Well, like I mentioned, the first step would be to quit smoking, to prevent further damage to the lungs. And also immediately on
cessation of
smoking you will not see any improvement. If there is bronchospasm, this can be relieved by bronchodilators. To improve lung function practice breathing exercises. If the oxygenation is adequate, supplemental oxygen therapy may be needed. Any infection of the lungs, need to be tackled immediately.