Writing a persuasive speech can be one of the most difficult tasks in your public speaking class. For a persuasive speech to be effective, you have to accomplish a difficult task: persuasion! It's much easier to write an informative speech or ceremonial speech than it is to write and deliver an effective persuasive speech that changes someone's mind or behavior.
Here are some tips to help you write a persuasive speech. Remember, your goal is effectiveness. You want to change people's minds and their behavior.
Find an appropriate and interesting persuasive speech topic. For many students, this is one of the most difficult parts of writing a persuasive speech. Set realistic goals. You're not going to change someone's mind about a major issue in eight minutes. You might change their mind about a smaller part of that issue. To be persuasive, you absolutely must identify with your audience and make your audience identify with you. This is so important, and yet many speakers don't try. Who are the members of your audience? What is important to them? Are they conservative? In order to write and deliver a speech that effectively persuades an audience, you need to understand who the audience is and what kinds of appeals might persuade them.
Use excellent evidence. Do your research, and pack your speech with lots of statistics, facts, quotes from credible people, and emotional examples. Remember, don't rely too strongly on examples as evidence. You can find an isolated example of just about anything.
Represent the other side accurately. When discussing the other side's point of view, make sure you are accurate. You need to accurately represent their motives and their point of view.
Find common ground with the other side. The audience will identify with you if they understand that although you have different opinions, you have similar goals and values. Then explain to them why you feel dress codes will actually increase student freedoms.
Ask the audience to take action-- and make it easy for them to do so. Hand out a petition for students to sign, or a self-addressed stamped envelopes to mail to someone. Make your action step as easy as possible, because most people are very busy and/or very lazy. Show the audience that you care very much about this topic. If the audience doesn't believe that you care, why should they? But you should not must, you should take their trust and help.
Good luck in your actions!