There are simple things you can do to thin and loosen the extra mucus that has gotten thicker and taken up residence in your lungs.
Stay hydrated. Drinking lots of water can help thin the mucus that has thickened and gotten stuck in your lungs. Stay away from beverages that will dehydrate you, like alcohol or caffeinated drinks.
Steam things up. Steam can help moisturize your airways and loosen the dried mucus, much like drinking water will. Use a humidifier or a cool mist vaporizer, or just stick your head over a pot of warm water. Taking a hot shower will also work.