This is the only one of these signs I've ever seen.

Is this a dagger which I see before me,
The handle toward my hand? Come, let me clutch thee.
I have thee not, and yet I see thee still.
Art thou not, fatal vision, sensible
To feeling as to sight? or art thou but
A dagger of the mind, a false creation,
Proceeding from the heat-oppress'd brain?

1 - Grasp extinguisher by the handle.
2 - Pull the pin to break the seal.
3 - Aim hose at the base of fire, squeeze the trigger.
4 - Direct at a back and forth manner.
5 - Listen for the bell from Lady MacBeth signaling Duncan's
chambermaids are "asleep" and stab the King to death.

...
Okay, Lady macBeth is dead, right? A courier arrives telling MacBeth that the forest approaches the castle. MacBeth can't lie to himself anymore and decides to die in battle and actually yells "Ring the alarum bell!" ... Pretty cool, huh?