It is a short book, but the difficulty is conceptual: the novel argues, in the first person, with a narrator who speaks to the reader all the time and who, in the first Books, barely recounts events. Whoever accepts the game follows along; whoever expects a plot from the first page may get lost.
The structure helps. There are eight Books and sixty-three short chapters, each with a title of the author's own, and the average is about two and a half pages per chapter. The longest, Chapter VIII of Book V, runs past two thousand words; the shortest are a little over a hundred. Each chapter has one idea or one scene that can be summed up in a line, such as the nose that leans, the mirror that winks, or the green blanket.
Books I to III are the most argumentative. In Book II especially, Moscarda addresses the reader, sits in his armchair and takes him for a walk, to prove that each person's reality is a form that someone gives. Chapter VII of Book III, a long parenthesis on facts, forms and acts as prisons, is the densest passage. In Books IV to VIII the action appears: the eviction, the donation, the shot, the judge.
For a beginner, the way in is Book I, which lays out the whole problem in eight chapters. What makes it hard is the tone: Moscarda calls himself lucid while seeming mad, and the book leaves the decision to the reader.