I am huge believer in keeping things simple with your presentation. Thus, I always advocate doing things in 3’s. Remember, the human brain works like this: 1, 2, 3, I forget.
Here is a photo from my Friday night flight on Southwest airlines. What I love about this napkin is that it keeps their message clear, simple, and to the point by using 3 icons: Board, Drink, Rewards. It’s memorable. It’s strong. It makes an impact.