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Breathe out as you normally would, then use your dominant hand to put the mouthpiece to your lips. Close your lips around the mouthpiece and let your tongue rest in the bottom of your mouth to keep it from blocking the mouthpiece. With the mouthpiece in your mouth, take a slow, deep breath in. There is a yellow piston or ball inside the column that will rise as you inhale. The goal is to make the piston or ball rise to the level indicated by the slider or marker. If you can’t inhale deep enough to move the piston or ball to the recommended level, don’t get discouraged. As you continue to use the incentive spirometer, your lung function will improve. Once the indicator has reached the desired level, hold your breath for as long as possible. Try to aim for at least 10 seconds. During this time, the piston or ball will slide back down toward the base. After holding your breath as long as you can, slowly exhale through your mouth into the incentive spirometer. You can then remove the mouthpiece and rest for a few seconds. If your doctor has given you specific instructions on how often to use the incentive spirometer, be sure to follow them exactly. Otherwise, aim for using the device 10 times per hour. Don’t forget to rest for a few seconds in between breaths to prevent lightheadedness. After using the device the recommended number of times, try to cough a few times. Coughing will help clear any fluid or mucus from your lungs and make breathing easier.

Summary:
Exhale and place your mouth around the mouthpiece. Inhale through your mouth until the piston reaches the marker. Hold your breath for as long as you can. Exhale through your mouth, then rest for a few seconds. Repeat 10 times per hour or as often as your doctor recommends. Cough to clear your lungs when you are finished.