Back in college, I was in the the Toastmasters club. For recruitment, we'd bring in a ringer from another club. This gentleman was an absolutely amazing "speaker". I put speaker in quotes because he transcended speaking. It was closer to a dramatic performance.
There are many tactical techniques that can get you to being a good speaker. To truly transcend, you have to treat your "speech" as a one-man play, with all the associated aspects: playwriting and acting.