I think that the assignment calls for you to mirror how Salinger's narration helps to construct the novel. For example, you would pick the item of importance and then discuss its importance, significance, memories attached to it in a manner that is more conversational, than anything else. Salinger's narration and Holden's discussions with the reader are not bound by a traditional structure. They are wide ranging and expansive. This helps to accomplish two elements. The first is that it shows how Salinger is conscious of not wanting to embrace traditional methods of storytelling in this narrative. Consider the opening lines of the work and the indictment of the standard Dickens form of narration. This style also helps to bring out how different Holden is in that his mind is almost like a field where there is little sense of structured guidance, but rather musings that are open to just about anything. In this, I think that the discussion of your object is to be told in this manner where there is not necessarily a structured narrative, but rather one that speaks directly to the reader thoughts and impressions from your own world in the hope of forging connection to their own.