Speeches are written for the ear, not the eye, and that single fact explains most bad ones. A reader can re-read a sentence; a listener gets one pass. So the craft of speech writing is the craft of being unmistakable the first time: short sentences, signposted turns, ideas that arrive one at a time.
A four-pass method
First pass: write the promise in one sentence and the landing in one sentence. Second pass: list your moves — story, proof, or ask — everything between those two sentences is one of these three. Third pass: draft at speaking speed, out loud, badly. Fourth pass: the director's cut, where you delete every line that does not serve someone in the back row.
Steal structure, not sentences
The linked templates are the same skeletons professional speechwriters reuse: And/But/Therefore for narrative, Problem → Proof → Ask for persuasion. Structure is not formula — it is the load-bearing wall that lets your own voice move freely around it.