"Few Italians have the true virtuoso spirit. For the most part their enthusiasm is adopted to suit the time and opportunity, to practice imposture upon the British and Austrian millionaires."

2. Conflict (inciting incident)
"The thousand injuries of Fortunato I had borne as I best could, but when he ventured upon insult I vowed revenge."

3. Rising Action
"It was about dusk, one evening during the supreme madness of the carnival season, that I encountered my friend. He accosted me with excessive warmth, for he had been drinking much." - Montresor initially greeting his victim.

"I passed down a long and winding staircase, requesting him to be cautious as he followed. We came at length to the foot of the descent, and stood together on the damp ground of the catacombs of the Montresors." - Montresor leading his victim to their final resting place in the catacombs.

"It was in vain that Fortunato, uplifting his dull torch, endeavored to pry into the depths of the recess. Its termination the feeble light did not enable us to see." - Fortunanato arrives at his tomb, as Montresor gets ready to spring.

4. Climax
In an instant he had reached the extremity of the niche, and finding his progress arrested by the rock, stood stupidly bewildered. A moment more and I had fettered him to the granite. In its surface were two iron staples, distant from each other about two feet, horizontally. From one of these depended a short chain, from the other a padlock. Throwing the links about his waist, it was but the work of a few seconds to secure it. He was too much astounded to resist. Withdrawing the key I stepped back from the recess.
- Montresor dropping his guise and stepping in for the kill.

5. Falling Action
"It was now midnight, and my task was drawing to a close. I had completed the eighth, the ninth, and the tenth tier. I had finished a portion of the last and the eleventh; there remained but a single stone to be fitted and plastered in. I struggled with its weight; I placed it partially in its destined position." - Montresor finishing his plan.

6. Resolution
"I hastened to make an end of my labour. I forced the last stone into its position; I plastered it up. Against the new masonry I re-erected the old rampart of bones. For the half of a century no mortal has disturbed them. In pace requiescat!" - End of the story and narration. 

When Montresor runs into Fortunato on the street, Fortunato is wearing multicolored motley and a cap with bells on it, which is the costume of jesters or fools in the old form of Italian theater known as commedia dell'arte. In the drama to come, Fortunato will be playing the part of a fool

The Vault

As Montresor guides Fortunato to the vault where he supposedly is storing the Amontillado, he guides him through a literal place of death. This is the Montresor family crypt, where members of the family are buried. There is an actual mound of bones in this catacomb. While one could store wine in a crypt—the physical conditions are similar—one would not expect wine that was recently purchased to be stored far, far back in this catacomb. There is wine here, but it is also a place of death, and bringing Fortunato here foreshadows his fate.

The Trowel

The Masons were a widespread fraternal organization that started as a medieval guild (for stonemasons, as the name indicates), but it grew into a more general social organization. There is a long history of anti-Masonic suspicion, and many stories have circulated about it being a secret society and even a mystical one. These attitudes grew so strong in 1826 that the Anti-Masonic Party emerged as a political party in the United States. The paradox here is that Fortunato shows by his hand gesture that he is a member of the organization, but when Montresor shows the trowel, he shows he is (or will act as) a literal mason. However, because Fortunato reads this as a joke, he misses the clue that he'll be entombed alive.

https://www.coursehero.com/lit/The-Cask-of-Amontillado/symbols/