338 15.6 speaKinG to inForM
stories for many reasons,” your more specific central idea might be “Three rea-
sons Lewis wrote the Narnia stories are to connect the ‘pictures’ he visualized
in his head, to write an engaging story for children, and to make a larger point
about Christianity.” Your central-idea sentence is your speech in brief. Some-
one who heard only your central idea would understand the essence of your
message.Generate Your Main Ideas
If you have developed a specific-purpose sentence and have a well-crafted
central-idea sentence, it should be easy to generate your main ideas. In our
C. S. Lewis example, we identified in our central idea three reasons why Lewis
wrote the stories. Those three reasons will become the main ideas of the speech.
The type of informative talk you are planning will influence your central and
main ideas. A speech about an object may lend itself to certain main ideas such
as history, features, and uses of the object, whereas a speech about a person
might be more likely to have main ideas related to the person’s accomplish-
ments or relationship to you, the speaker.Gather Your Supporting Materials
The type of informative speech you plan to make will often suggest ideas for
supporting materials. Biographical details and stories will most likely support
a speech about a person. Stories, examples, or statistics may help you to teach
your audience about an event or idea. Remember that supporting materials
include presentation aids. As we noted earlier in this chapter, visual aids often
make speeches about objects and “how to” speeches about procedures more
effective. As you gather supporting material, continue to think about your audi-
ence, who will ultimately judge whether your supporting material is interesting
and helpful.Organize Your Speech
In developing a specific purpose and identifying main ideas, you’ve already
been working on the organization of your message. As you keep your audience
in mind, you now determine what the best sequence of your main points should
be. Your topic and purpose can also help guide you. As we discussed earlier in
the chapter and in Table 15.1, different types of informative speeches lend them-
selves to different organizational patterns.Rehearse Your Presentation
For informative speeches, it is especially helpful to rehearse in front of other
people, especially people who are similar to your listeners, if possible. Seek their
feedback about whether you are effectively teaching them about your topic. You