I often hear people say, "I want to speak like Mr/Mrs X."
Yes, observing experienced speakers can be informative but don't mimic them. Every person has their own speaking style.
An effective way to develop your speaking style is simply to speak in simple terms. It's like writing—don't try to sound intelligent, or adopt a particular style of prose, or you'll end up sounding like a second-rate version of someone else.
Just communicate the message clearly and simply, and over time, your 'voice' or 'style' will naturally emerge.