Here are three traits of improvement to learn how to be a masterful communicator (Masterful Communication is one of the ten PLI Essentials...)
How do you get there?
Confidence as a communicator is achieved through specific experience (understand what type of communication you need to be great at and then practice that) and by keeping your focus on others (the less you think about yourself, the less you think about how you can't do something or don't know something, etc.)
Clarity is achieved by communicating in concrete terms and by keeping your message very simple. Every communicator and speaker should read, re-read, and then re-read again Made to Stick by Chip and Dan Heath.
Commitment is achieved by deciding to deliver every time you have a communication experience that you know you need to hit out of the park and by deciding to improve your communication abilities every day.