This is the method I use to teach public speaking. It has proven very successful in building skills and confidence in my students. I use a technique that combines learning the fundamentals of enunciation, grammar, and vocabulary (to build language skills), methods for projecting the voice, breathing, and timing (to grab and hold attention and make yourself heard and understood), and elements of relaxation and confidence (to overcome any anxiety). Then there is a good deal of practicing of these techniques through role playing of speeches, talks, interviews, and discussions. I think you'll find that my methods work very well.