Wash your hands with soap and water for at least 20 seconds. Check the expiration date on the canister of your inhaler. Remove the cap from the mouthpiece. Shake your inhaler up and down for five seconds. Then prime it, if needed, by facing it away from you and pressing down on the canister three times. Stand up straight, or sit up straight. Breathe in once, breathe out once. Place the mouthpiece between your lips and press down on the canister, breathe in for five seconds. Remove the inhaler from your mouth and hold your breath for 10 seconds. Place the cap back on the mouthpiece. If your inhaler used a steroid, rinse your mouth with a sip of water and spit it out.