Any time we communicate, our deep-down goal is to impress someone. We want them to follow us into battle or buy our product or agree with our choice for lunch. If we don't impress them in some way, they are less likely to go along.
Three ways to IMPress our audience
When we say something surprising, we challenge our audience to interpret this new information. In many parts of a presentation, the element of surprise brings benefits. In the beginning, it can create energy. Throughout the presentation, you can plan some small surprises to keep everyone awake. And you can build up to a grand surprise in your closing.
Ask questions, even if they are rhetorical. In small groups, use their names. Schedule a "break" where they can discuss the topic with their neighbors for 2 minutes. I've even seen presenters ask for input on the order they will talk about the agenda items. Anything we can do to let the audience feel a sense of responsibility helps us to impress.
Make them IMPortant
Your audience needs to feel like they are the reason this presentation is being held. Because they are! Without them, we would be presenting in front of a mirror, with no chance of influencing anyone. Show respect by not wasting their time and by focusing on issues that they find important.
Three ways to IMPress our readers
Make every word count
Our readers are busy people; don't waste their time with long sentences that carry a lot of dead weight. Choose strong words and match those words with simple but precise grammar.
In business, we aren't writing a detective novel. We want the reader to know what's going on as quickly as possible. Solve the biggest issue early in the report. A certain amount of politeness is necessary, but make sure that it doesn't obscure the message.
Say "Thank you"
Even if it is for something simple like thanking somebody for an earlier email, it makes an impression. If we thank somebody in advance*, it puts some pressure on them to do something.
*Bonus advice: Do not use the expression "Thank you in advance." "Thank you for helping me on this" gives it an air of assumption that is hard to ignore.