The actress spent more than an hour each day transforming into Elvis Presley’s bride for the new Sofia Coppola movie

Cailee Spaeny (left) stars as Priscilla Presley in ‘Priscilla’ (right). Photo: GABRIEL BOUYS/AFP via Getty; Sabrina Lantos/A24

Transforming Cailee Spaeny into Priscilla Presley for Sofia Coppola’s Priscilla was a team effort.

The actress tells PEOPLE she spent about an hour and a half with the movie’s hair, makeup and wardrobe departments to become the woman who captured Elvis Presley’s heart.

“They worked incredibly hard,” Spaeny, 25, says of the creative teams.

In the film, the Springfield, Missouri, native plays Priscilla from age 14, when she first meets Elvis, to age 27, when she finally decides to leave him.

The change in age is illustrated through Priscilla’s various looks: At 14, she’s a fresh-faced high school student. But the more time she spends with Elvis and gets absorbed into his world, the more she transforms with heavy eye makeup and towering bouffant hairstyles.

Elvis and Priscilla Presley’s ‘Wild’ Romance and the True Story Behind Priscilla (Exclusive)

Cailee Spaeny as Priscilla Presley in ‘Priscilla’.Sabrina Lantos/A24

Costume designer Stacey Battat told reporters at the New York Film Festival that it’s like “a child playing dress-up.”

Indeed, in Elvis and Me, Priscilla’s 1985 memoir that Coppola used as the basis for her screenplay, Priscilla wrote about how Elvis, who was 10 years her senior, often picked out her clothes and nixed things he didn’t like. (For instance: solids only, no patterns).

Cailee Spaeny as Priscilla Presley in ‘Priscilla’.Ken Woroner/A24

“He taught me everything: how to dress, how to walk, how to apply makeup and wear my hair, how to behave,” Priscilla wrote, adding, “I was Elvis’s doll, his own living doll.”

The makeover helped Spaeny get into character, she says. “When you walk into a set and you’re wearing those kinds of costumes, a lot of the work [is] done for you. It’s a gift.”

A young Priscilla Presley.Bettmann Archive/Getty

Some of the wigs were “heavy,” Spaeny admits. “Every time I got into a car, even though they told me, ‘Watch your head,’ you have to be aware of the physical space around you in a different way,” she says. “That was actually really fun.”

“It was a missing piece to the puzzle and was really so informative of how I was going to move at different ages and stages of her life,” she continues. “The beehive on your head, and having heels on and little dresses, you sort of move like a doll.”

Never miss a story — sign up for PEOPLE’s free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories.

Priscilla Presley in 1963.Michael Ochs Archives/Getty

The teams took care to reimagine Priscilla’s “iconic” looks, like the one from her family photo shoot after giving birth to daughter Lisa Marie in 1968. But Spaeny says they were “always racing the clock” due to the time constraints of filming an independent movie on a tight schedule.

When Spaeny was getting ready to film that family scene, she recalls it was getting late. “We were losing light that day,” she says, “and it was a moment where producers had to come in and say, ‘Put the brushes down. We have to go.’”

See Priscilla Presley’s Life in Photos: From Marrying Elvis to Opening Graceland

Priscilla Presley in 1974.Ron Galella/Ron Galella Collection via Getty

The actress also had the opportunity to spend time with Priscilla herself, now 78, to watch and master her mannerisms and movements.

“She’s a woman from a different era,” continues Spaeny. “She has, which you pick up on when you’re with her, she has this softness about her. She’s very delicate on the surface, but she has such fierceness in her as well.”

Priscilla is now in theaters.