Anyone can have an opinion, but in order to write an effective opinion paragraph, you must be able to support your opinion with reliable information and organize it in a coherent manner. Doing this well gives you a chance to influence the opinion of your reader. Once you have researched the topic, and know what information you wish to use, structuring the paragraph is simply a matter of organization.
Include the topic, as well as your opinion, in the very first sentence. Since a paragraph is only a few sentences long, you cannot waste any time getting to the heart of the matter.
List each of your supporting facts in a different sentence. Explain how each fact supports your original stance. You should use no more than three to five facts, and write no more than two sentences for each fact.
Close the paragraph by restating your opinion, while rewording it slightly to incorporate some of the information related in the rest of the paragraph.