Conclusions wrap up what you have been discussing in your paper. After moving from general to specific information in the introduction and body paragraphs, your conclusion should begin pulling back into more general information that restates the main points of your argument. Conclusions may also call for action or overview future possible research. The following outline may help you conclude your paper:
In a general way,
Restate your topic and why it is important,
Restate your thesis/claim,
Address opposing viewpoints and explain why readers should align with your position,
Call for action or overview future research possibilities.
Remember that once you accomplish these tasks, unless otherwise directed by your instructor, you are finished. Done. Complete. Don't try to bring in new points or end with a whiz bang(!) conclusion or try to solve world hunger in the final sentence of your conclusion. Simplicity is best for a clear, convincing message.
The preacher's maxim is one of the most effective formulas to follow for argument papers:
Tell what you're going to tell them (introduction).
Tell them (body).
Tell them what you told them (conclusion).