The techniques of spirometry include taking a deep breath before blowing, holding the mouthpiece close to the mouth, and maintaining emotional stability. 1. Breathe deeply before blowing: Before the spirometry test, take a deep breath and exhale evenly into the mouthpiece. This will increase the volume of air in the lungs, and the measured spirometry value will be larger. 2. Tighten the mouthpiece: During the spirometry test, you can tighten your mouth and the mouthpiece. If there is a big gap between your mouth and the mouthpiece, it may lead to air leakage, and the measured spirometry value will be small. 3. Maintaining emotional stability: You should not be too nervous before the spirometry test. Maintaining emotional stability will help the examinee exhale more gas and improve the test value. The spirometry test should try to blow out as much air as possible, reflecting the individual’s maximum pulmonary ventilation. If one’s own lung capacity is small, daily training can be done by expanding the chest and adhering to aerobic exercise.