BOURBONNAIS — Matt Nagy’s hotel room opened out onto a cliff perched high atop his favorite vacation spot: the eastern Caribbean island of Saint Lucia.

Three weeks after the Bears’ season ended in dramatic fashion, he’d escaped there for a week with his wife — no kids — in late January. He’d return only to receive his NFL Coach of the Year Award the night before the Super Bowl.

In his room, Nagy opened a book that would come to define the way the Bears prepared for his follow-up season: “Legacy,” by James Kerr. The 2013 book details 15 leadership lessons gleaned from New Zealand’s dominant national rugby team, the All Blacks. Packed with peculiar phrases — “sweep the shed,” “keep a blue head” and “follow the spearhead,” among others — the book hooked the coach high up in his hotel room.

“I’d just sit up there and read it,” he said.

Soon, others did, too — Bears front-office members, coaches and scouts, one of whom handed Nagy 10 pages of card stock filled with notes. Nagy typed his thoughts into his phone. Some book pages took him three or four minutes to read because he wanted to make sure he absorbed every word.

Nagy preached the book’s tenets to players during organized team activities and again during the start of training camp. Many players have read at least part of the book, which was first suggested to Nagy by the father of quality-control coach — and former Nagy high school quarterback pupil — Mike Snyder on a visit to Halas Hall.

Each offseason, teams adopt new mantras to try to build up their culture. Nagy’s “Be you” catchphrase was painted in a Halas Hall hallway last year. Sam Walker’s book “The Captain Class,” which general manager Ryan Pace gave to then-rookie Mitch Trubisky in 2017, spawned a relationship between the author and the quarterback.

Each year’s theme provides insight into where the franchise believes its season is headed. Two years ago was about grooming Trubisky. Last season was about wholesale change: a new coach, offensive staff, playbook and culture.

This season, with the Super Bowl in mind and most of their roster in place, the Bears are descending into the particular.

“That was big-picture last year,” Nagy told the Sun-Times. “Now we’re able to tackle other areas. That’s what we’re doing right now — we’re hammering through the details.”

‘Sweep the shed’

When the Bears checked into Olivet Nazarene University last week, Trubisky raised eyebrows when he was asked which detail he wanted to improve upon.

“I think it could be as simple as cleaning up in the locker room,” he said.

Trubisky hadn’t turned into Marie Kondo. He was parroting a tenet of “Legacy” — “Sweep the shed.” The book explains how the All Blacks’ rugby stars clean their own clubhouse at the end of games.

“It looks the way it did when they got in there,” Nagy said. “That’s what it’s supposed to be like. That’s going to transfer to the football field — and off the football field.

“I’m glad that Mitch connected that.”

Nagy plans to use a symbol during the season — a broom, perhaps — to remind players of the saying.

Guard Kyle Long compared the concept to Admiral William H. McRaven’s “Make your bed” mantra, which encourages people to conquer their first task of the day.

Long throws away his plastic water bottles and wrist tape. Cornerback Prince Amukamara tosses his cup filled with sunflower seeds in the proper bin. Players remind each other to do the same.

“If you treat your environment with respect, you’re going to treat your playbook with respect, you’re going to treat your teammates with respect,” Long said. “You’re going to be on time. You’re going to do the right thing when it’s needed.”

Cornerback Kyle Fuller interprets the phrase more broadly: “Just do the little things.”

Regardless, “sweep the shed” is a three-word concept that’s, well, sticky. Players remember it. It fits on a sign or a T-shirt.

“We’re smart enough to understand the concept of ‘sweep the shed,’ ” Long said, “and just dumb enough to not know where it stems from.”

‘Leaders create leaders’

When they played in a celebrity golf tournament in July, former star running back Marcus Allen told Nagy his best teams were always led from within. It reminded the coach of his favorite “Legacy” phrase: “Leaders create leaders.”

When Nagy took over the Bears, he became their focal point.

“The way I look at it is, they were looking for a leader last year,” he said. “We as coaches, we try to lead.”

Now it’s the players’ turn. Trubisky is first in line.

“The really great teams are good at the little things,” Trubisky said. “And that’s what we’re trying to focus on.”

Each of the Bears’ three quarterbacks has read at least part of the book. It comes with the position.

“It might not always be the guy on the field that’s the one that’s making the culture right,” quarterback Chase Daniel said. “So as a backup, you sort of take that to heart a little bit — ‘Hey, there’s more than you can do than just on the field.’ It’s off the field, helping guys.

“What we want to really do is breed culture here. That’s what they’re all about.”

‘Continuing ed’

Amukamara has played on teams that felt like a military academy and others that felt like liberal, private school. He has seen coaches lean on books ranging from “The Art of War” to “The Energy Bus” to motivate players. He has heard hundreds of catchphrases.

Nagy’s stand-by tenets — “Be you” and “Club Dub” and “Swag” — are his “non-negotiables,” Amukamara said, as embedded into the team as their fight song. Other phrases, he suspects, might have been cribbed from Nagy’s former boss, Andy Reid.

“Now,” Amukamara said, “he’s adding some of his own stuff.”

Nagy calls the book part of his “continuing ed.” Lessons learned include “Keep a blue head” (to keep calm during tense situations) and “Follow the spearhead” (to work together with your teammates).

Nagy is fond of another All Blacks mantra, too: “No d---heads.” He repeats that to his own team.

“Normally at the beginning of my team meetings, whether it’s OTAs, whether it’s the start of training camp, they know, they get the message,” Nagy said. “Every player on this team is high character. That book is about character and how you do things.”

By starting with a mature team, Nagy has given the mantras a chance to stick.

What started in New Zealand and reached Nagy in Saint Lucia has landed in Bourbonnais.

“When you have veterans take ownership of the culture that the coach and management is trying to instill,” Amukamara said, “I think that’s when it becomes more powerful.”