When you’re giving someone directions, it’s not enough to provide the correct information — the order of your words matters too.

Starting your sentence with a noticeable landmark and ending with the desired place is more effective than when the order is reversed, a study published in Frontiers in Psychology found.

Researchers discovered this practical bit of advice with the help of an unlikely source: the popular children's book, "Where's Waldo?" Researchers asked participants to search for the cartoon character wearing a red-and-white striped sweater amid a large, detailed illustration. They asked them first to find Waldo and then to provide instructions on how to find him quickly.

As expected, most people described Waldo’s location in relation to a landmark, such as a building. But researchers were surprised to learn that participants put their words in a different order depending on the landmark — and that fork in the road made a difference. Imaging software determined the most noticeable landmarks. The most prominent places were more likely to be mentioned at the beginning of the sentence, whereas less prominent landmarks were cited at the end of the sentence.

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“Here we show for the first time that people are quicker to find a hard-to-see person in an image when the directions mention a prominent landmark first,” University of Aberdeen researcher Alasdair Clarke said in a news release. “As in ‘Next to the horse is the man in red,’ rather than last, as in ‘The man in red is next to the horse.’”

In the second part of the study, the researchers tested participants' ability to find Waldo by listening to directions in which the order of the words varied. They found that the most effective method was when the directions started with a landmark.

This suggests that when people receive directions, they keep a mental record of which objects are the easiest to see, such as landmarks, and they treat these differently than objects that are more difficult to see, such as Waldo.

"Listeners start processing the directions before they're finished, so it's good to give them a head start by pointing them towards something they can find quickly, such as a landmark,” said study co-author Micha Elsner. “But if the target your listener is looking for is itself easy to see, then you should just start your directions with that.”