1. Shake it strongly till the sound can be listened.(about 10 times) 2. Install button with nozzle into the can. 3. Spray it in the air shortly before using. 4. Use it in vertical position. 5. It can not be used-up if it was in a tilt or an inverted position. 6. Set the nozzle in the keyhole about 5mm and spray it for 0.2 seconds.