Complex sentence: To extinguish the lamp turn down the flame and them blow across the chimney to put out the flame you can also extinguish the lamp by quickly turning down the wick below the top of the wick tube.
Split into simpler sentences: To extinguish the lamp turn down the flame and then blow across the chimney to put out the flame. You can also extinguish the lamp by quickly turning down the wick below the top of the wick tube.