Wash or sanitize your hands
Assemble the spirometer if needed
Sit upright with your feet flat on the floor
Hold the spirometer level
Exhale normally
Place your lips tightly around the mouthpiece
Inhale slowly and deeply through the mouthpiece
Raise the indicator or piston to the target level
Remove the mouthpiece and exhale normally
Rest for a few seconds
Repeat the exercise as instructed
Clean the mouthpiece after use
Record your results if required