The structure of you paper is very important. I should be able to follow your line of reasoning from the first sentence to the last without getting lost, confused, or sidetracked. Wonderful ideas aren't worth much if it is not clear how they all fit together.
Argument. In its most basic form, your paper should be an extended argument, the conclusion of which is a statement you are asserting to be true. An extended argument is one that incorporates one or more sub-argument into the main argument. For example, your main argument may have four premises which lead to your conclusion. If, however, your premises are slightly controversial, not obviously true, or not common knowledge, you should provide sub-arguments to support your premises. Moreover, the premises which support these sub-conclusions may need arguments of their own. Thus, an extended argument is a series of embedded arguments, ultimately leading to your main conclusion.
Thesis. The thesis is a statement that is the conclusion of the main argument of your paper. Every paper should have a thesis. Your thesis should be clearly stated at the beginning of your paper in the introduction.
Introduction.The introduction to your paper has at least two purposes. First, you need to tell your reader what your conclusion will be. This is your thesis statement. Second, you need to tell your reader roughly how you will get to this conclusion. This is not a detailed outline of your paper, but rather a concise summary of the steps in argument.
Body of the paper. The body of the paper comprises the argument for
your thesis. Each paragraph should be a step in the process of supporting your
final claim. This process has several parts:
Conclusion. Contrary to what you may have learned in High School, your conclusion should not be a restatement of your introduction. Rather, the conclusion is a handy place to tie up loose ends. Here is where, for example, you can consider objections to your argument to which you do not have the space or expertise to respond. This is also a good place to briefly consider the implications of the acceptance of your conclusion. Or this may be a good place to explain what further work may need to be done in this area.