If you want to speak with competence, confidence, and clarity, you need the four Ds. In his book Speaking to Win
(AMACOM), Brian Tracy discusses the four key elements:
You must have an intense, burning desire to speak well. If your desire is strong enough and you want to achieve speaking mastery long enough, nothing can stop you from reaching your goal; but desire is not enough.
2. Decision. You must make a decision this very day that you are going to make every effort, overcome any obstacle, and do whatever it takes to become excellent.
3. Discipline. You must have the discipline to plan, prepare, and deliver talks and presentations, over and over again, until you achieve mastery. There are no shortcuts to hard work in developing an essential skill.
4. Determination. You must have the determination to persist and persevere in spite of any short-term setback, obstacle, or embarrassment you may experience.