When preparing for a speech with toastmasters, I found that the manual suggested that I use some rhetorical devices. 4 rhetorical devices were listed and I wasn’t very impressed with them. I went off and did some reading on the subject.

Simile: ‘Albert Einstein is like a god in physics’
Simile is useful for descriptions. It’s tough to not use them when describing anything. You can start describing an objects attributes, size and shape and such. But it easier to compare the object to something that the audience already knows. “A ship is like a boat, but much bigger.” This tells the audience a lot more than a physical description of a ship.

Metaphor: ‘Albert Einstein is a god in physics’
Instead of saying that something is like something else, you say that it is something else. ‘Nuff said.

Alliteration
I like Alliteration. My name is alliterative. When I was 18, I discovered that I had scoliosis. My back was bent the wrong way. This led me to: Stephen Squire’s scoliotic S–shaped spine.

Triads
This is to say things in 3s. Be careful this because can be either impressive or stupid. I came, I saw, I conquered. Or in the original Latin: Veni, vidi, vici.

Hyperbole: “Anyone who leaves litter in a park is worse that Hitler.”
Hyperbole is to greatly exaggerate or overstate.
I was tempted to write something like “Hyperbole is the greatest rhetorical tool in the universe”.
I wouldn’t have been the first to use that gag.

Allusion
A short, quick reference to a famous person or work. “There is a special ring in Hell for people who litter in parks.” This could also be filed under hyperbole. Special note: make sure that your reference is famous to your audience. If they don’t know about Dante’s Inferno, then the reference is only confusing.

Rhetorical question (erotesis)
We’ve all heard this. “How stupid are you?” “Why do I even bother?” “Who hasn’t thought about robbing a bank?” Maybe not.

Repetition. ‘The 3 most important things in real estate are location, location, location’
There are a number of ways of doing this. You can repeat the same word. You can repeat a phrase. You can repeat a whole sentence.
Typically, saying the same thing twice isn’t always noticed. Saying it 3 times or more is what gets attention.

Hypophora
A different kind of rhetorical question. In this case, the speaker asks and then answers a question. “How can we save money? We’ll do it this way”
I was impressed when I found this one and mentioned it to my wife. She said “No kidding. You’ve used it in all of your speeches.” It turns out that I’ve used it to break up the pace between the body of my speech and its conclusion. Something like: “What are you to do with the information that I’ve just given you?”

ExpletiveThe first that I’d heard of expletives was when I was reading transcripts from Nixon’s Watergate tapes and the term “expletive deleted” was added to the public lexicon. My first thought on reading that expletives were rhetorical devices was that they can be used for some damn fine rhetoric. This, in fact, is not the case. The way that I tossed in the words “in fact” is an example of an expletive. This, indeed, was disappointing.