Several years ago in one of my high school level latin classes, I recall a discussion about techniques used by the Roman orators. My memory is rather hazy on the matter, but I think these sort of "tips" were mentioned: saying things in threes (i.e. "We must fight for love, liberty, and freedom!"), using gestures/body language to help convey your points (open palm beckoning the crowd while inquiring, slamming a fist to put emphasis on something), etc.
Anecdotes aside, what sort of techniques were used by Greek or Roman orators?
If anyone could give me some further insight into the matter, and potentially some sources that I could skim, I would appreciate it!
edit: Changed wording
In short, what sort of techniques were used by Greek or Roman orators?
There isn't really any short version. Oratory was, along with verse, the singlemost studied and complex literary form of the ancient world. Entire careers were spent perfecting particular styles or sub-styles, schools of rhetoric were the most sought-after educational institutions since at least the sophists. We have entire handbooks on rhetoric and oratory, most of them quite lengthy--Quintilian's surviving Institutio Oratoria (to say nothing of his many lost works on rhetoric) is 12 freaking books, and Cicero's de Oratore is three. That, without even mentioning later grammarians and the late rhetorical tradition under people like Augustine. To sum up rhetoric and oratory is like trying to sum up the entirety of Classical literature--in many ways it is Classical prose, since pretty much all prose writing used the rhetorical principles of oratory as its foundation. If you're interested in gesture there's an old thread that might be of value to you, although it's really just asking whether gesture was used. The other thing you mention, saying things in triplicate, is what's known as a tricolon. A favorite technique of Cicero's was the tricolon crescendo, which he often combined with his clausulae--the tricolon crescendo consists of a tricolon in the final position of the sentence, often separated by periodicity from the rest of its mother clause, in which the orator doesn't just create a tricolon but with his prose rhythm, tone of voice, and gesture creates an enormous rise in tension to complete and hammer home a rhetorical point. Cicero often gets carried away with his, my adviser once described them as being the hysterical outbursts of a man who knows he has no argument but is going to argue anyway. But oratory is an entire field of study in and of itself, with a complex and specialized terminology, and it's really pretty hard to simply sum it up within the confines of reddit--Quintilian couldn't even do it in 12 books! Without some more specific point there's really not that much that I think we can help you with
Here are some:
Flatter. Along the lines of "My good people..." "Brave people of Somecity, I'm here with you today to..."
Use of uncertain words / generality. Speak and promise things in a way that different people can interpret / understand to mean something different, so each listener listens what he wants to listen. That will make more people support you, and it will also give you an excuse once you done something, to say to those who thought that you would do something else, that you didn't lied to them, but that it was them who didn't understood well what you were saying.
Try to convince people by provoking sentimental reaction instead of targeting their reason and logic. It will be way easier to just make people agree to something because they feel that this should be done, instead of making them think that this is the right thing to be done.
source: Plato's 'Gorgias' book.