The task of writing a speech may seem daunting, but with some practice and dedication, you'll soon have a good grasp of the necessary skills. You have many things to think about that don't necessarily come into play when writing for a reader. Think about how your words will sound when spoken aloud, and strongly consider the persuasive effect your writing will have on an audience. In most cases, when writing a speech, you are trying to change someone's mind about something, so you have to analyze your arguments from both sides and consider ways to strengthen them.
Think about the audience you're speaking to and how they feel about different issues. If you want to persuade people, you'll need a good understanding of their views, and you'll need to know how to speak to them.
Decide on a topic. You need to find something worth speaking about that will interest your audience. Brainstorm and write down anything you can think of on a piece of paper, then select the topic that seems most suited to the situation.
Do your research. Study everything available on your subject until your knowledge is very complete. Try to find sources of the highest quality. You wouldn't want to make a blatantly false statement in your speech because of a poor source.
Study the opposition. If it's a contentious subject, you need to understand both sides of the basic argument.
Determine how long the speech needs to be.
Create an outline. This will serve as a skeleton of your speech, where you can determine the ideas you want to cover and lay out the structure. At the very beginning there should be an introduction, and at the end there should be a summary. The ideas and arguments of the speech should be sandwiched in the middle.
Start with the middle of your speech where your major ideas are covered. Write as if you were talking to people. Read your words aloud and see how they sound. If they're stilted and uncomfortable, adjust them until they sound good when spoken. Make sure your language is persuasive. Think about how it would feel if someone were saying the things to you. Is it condescending? Is it friendly, or angry? Make adjustments.
Continue this process on each idea until you finish the main parts of your speech.
Make sure each of your ideas flow from one to the other. If the changes seem abrupt, insert little transitional statements between sections.
Write your ending. Make it memorable. Usually, there will be a call to action and a general summary of the topics you've covered.
Write your introduction. You need a hook of some kind, maybe a statement that shocks people or makes them laugh. You want something that immediately generates intense interest.
Read through your speech several times to make sure everything is working, then read it aloud and make sure it all sounds good when spoken. If there is anything wrong, make adjustments until it feels right.