Remember to keep each supporting paragraph focused on one main idea . Finally, transitions are helpful to readers, both within paragraphs and between paragraphs. A conclusion is different from a summary. A summary ticks off points already made in the paper, while a conclusion pushes the reader to consider the larger significance or urgency of what has just been argued. The trick is to do this without sounding preachy or soap-boxish.
Most writers have to rewrite their conclusions several times before they find something that works.
That's why you're in this class, and that's why I'm here, too.