On the other hand, your paper should not have too little content, so that you either repeat yourself or go off on tangents. Learn to use examples, facts, and logic instead of padding. The reader should be able to tell from your introduction how your paper is organized. Obviously, you must know which kind of paper you are writing, and the organization should be reflected in your introduction and thesis. The reader should find it easy to follow your train of thought through the paper, and the conclusion, if required, must follow logically from what has gone before.
Smooth transitions are a part of organization.
If your instructor has given you exact instructions for organizing a specific paper, be sure you follow them. Mechanical errors of every kind detract from a paper. Your goal is to have none. The more errors, the fewer points you earn for mechanics. Good expository writing should be clear and easy to read.