Gather all information for the speech. Regardless of the type of speech, it is crucial to become a subject matter expert on all the topics related to the speech. Fancy slides and music will not cover up a lack of knowledge. Do the research, and address all possible questions that could be brought up by the audience. If the topic of the speech is computer operating systems, for example, knowing about Windows will cover only part of the speech. The speaker should know about Macs and Linux as well.
Determine a demonstrative manner for the speech. This includes any tools you will use to complement your speaking. PowerPoint slides are an opportunity to use pictures, flow charts or parts of the actual speech to enforce what is being said. You can also use role-play by the audience or persons brought in by you to enhance a demonstrative speech.
Document all the steps in process of the demonstrative speech. Cover all the areas that will educate the audience concerning the topic. Include additional props that will be a part of the speech in the appropriate areas. To continue the example of operating systems, you would include screenshots of each operating system at various steps in executing simple programs.
Rehearse the process in its entirety. This means that the entire presentation must be ready to go before the actual speaking engagement. The outline should be descriptive enough to clearly lay out what is happening at every step in the process of the speech. Handouts and any other props that you will use in the speech should be ready for delivery to the audience.