Study your audience. Like any piece of effective writing, you should have a strong sense of who is reading the piece. This will help you to best appeal to their interests and convince them to share your view. For example, if you are writing an exhortation proposing a reformation in an institution, you might write a very different paper for the leaders of the institution than the members.
Research the subject matter. If you are writing an exhortation, it is likely that you already have an opinion on something that you want to share with others. The best way to communication why the reader should feel the same way is to prove that you have done your homework. Find supporting details that defend your argument and reputable sources for your claims.
Write an introduction that includes a well-developed thesis statement and introduces the subject. Your introduction should instantly grab the reader's attention, either with a quote, anecdote, statistic or a lead that will draw on their emotional connection to the topic.
Include supporting details that defend your stance. Add presence to your argument with in-text citations such as excerpts from books or quotes from respected thinkers that support your stance. Consider what information drives you to feel the way you do. Including these facts will personalize and empower your writing.
Conclude with a final plea that calls the reader to act. Now that your audience is knowledgeable of your point a view, they should know how to proceed. Define this clearly in the final passage because this might be your last chance to reach the reader on the subject.