One of my mentors, Tom Mendoza, taught me that if you work on public speaking you will be better than 90% of your peers. I recommend this video from Tom talking about the value of public speaking as well as techniques he uses when he speaks.
I am regular listener of the EntreLeadership Podcast. The host, Ken Coleman interviews many great leaders and authors. In an episode from 2016, Ken shared his ideas on how to improve how you say it. My summary of his podcast is below.
Work on enunciation
Vary your pace
Master the use the pause
Practice use of changes in intonation
Work on getting rid of fillers and crutch words
Demonstrate energy or passion
Combine two of the above such as change of pace followed by pause for even more emphasis
Early in my career I had to um, ah, practice not using filler words. I also had to get comfortable using the pause. If you did not have a chance to listen, I recommend you listen to the podcast starting at 36:39.
One technique that has helped me, has been to record my presentations on my iPhone and listen to myself talk. This has help me improve tremendously. Another technique has been to practice my presentations standing up or even in front of a mirror. What do you do to improve how you say it?