Be sure your thesis stands out as the central idea or your purpose stands out as the controlling statement. When used, each of these provides the basis for structuring the body of the discourse. Use a division of thesis or purpose to list your main points. Structure your audience as well as your speech with these main points. One of the central differences between spoken and written discourse is the high degree of structuring that is necessary to map an audience through a speech.
Readers can go back, review, and re-read the message.
Listeners do not have that option. This has attention and interest value. Do not use the introduction to apologize, antagonize, or offend. In the conclusion use relevant material also that relates to the subject, audience, or the occasion. The conclusion is the place to summarize the whole thrust of your speech including the restatement of your thesis.