Informal writing often calls for a modified form of the classic argument structure described above. Once you have an introduction and a conclusion, you can combine and move any of the other parts around to suit your audience and purpose. For example, you can combine the introduction and the statement of your proposition, refute the opposition's major and strongest point, state your case and confirm your proposition, refute the opposition's weaker points, and end with your conclusion.
We understand the way in which audiences assimilate new information and come to understand and accept new points of view. Your argument can reflect this. Readers usually start with a state of ease and comfort with their own understanding and points of view. As you introduce new information and question their beliefs and understanding, your readers enter a state of discomfort and a cognitive disorientation. At this point, the writer can help the audience assimilate new information and new points of view by providing relevant examples and clear evidence that builds on what they already know.