One effective way to introduce a right-brain break is to use one of what I call "the three magical phrases." When I'm giving a presentation and tell people there are three magical phrases, they immediately get out their pads to make notes—no matter how many credentials they have or how experienced they are as speakers. That's because everyone wants an easy fix to be a better speaker. This is, in fact, one easy fix. And these magical phrases are: "It's like...," "For example...," "Just imagine...."
Those three phrases are perfect to get your audience's attention and lead them along the path you want them to follow. Suppose you're making a presentation trying to get your colleague to participate in a blood drive. You could make the presentation by stating all the facts about how many people need blood donations every day and how depleted the blood supply is. But think about how much more effective you could make your appeal by adding: "Just imagine that your loved one is in trouble and in need of blood, and there is not enough to go around." That right-brain example is more likely to lead to action than just the facts alone. (By the way, I used the right-brain trick by starting the sentence before last with "But think about....")
Here's a good use of the phrase "it's like." I once read an article in the New York Times about a probe flying to Jupiter at 106,000 miles per hour. That speed was beyond my comprehension; it did not spur my imagination at all—until the next sentence, when the author wrote that it was like going from New York to San Francisco in a minute and a half. Then I was able to picture myself sitting down in a plane, taking a deep breath, and winding up in San Francisco. The simple phrase "it's like" is a powerful example of the effect your choice of words can have on a presentation.
Examples also add power to presentations. Use them whenever you can. Suppose you wanted to tell your audience that we all have a huge amount of potential inside us; we just have to let it out. You could then add: "For example, Michelangelo claimed that he didn't create his statutes, but rather released them. Find a slab of marble, he told his younger artists, then take away everything that isn't the statue." Every time you say "for example" in a presentation, the audience's interest perks up. They know you're going to explain your idea in a different way, or a better way, or make clear something they didn't understand the first time around.
If you use the phrase "just imagine," use it only once or twice, because it stands out and people will notice if you repeat it too often. You can use "it's like" or "for example" more frequently without it becoming obvious.