If you are called on to use your extinguisher to fight a fire, just think of the words, PASS:
PULL on the safety pin at the top of the extinguisher.
AIM the nozzle, horn, or hose at the base of the flame (6 to 8 feet away).
SQUEEZE or press the handle.
SWEEP from side to side at the base of the fire until it goes out.
Always follow the manufacturer's instructions as listed on the unit. Never go back into a burning building!