"I was trying to do something that would again be iconic, simple, realistic, but not overdone," says Star Wars' chief hair designer
Credit: David James/Lucasfilm 2015 LTD.

How do you follow up Princess Leia’s famous sidebuns? For Star Wars: The Force Awakens, the hair-and-makeup team invented “The Three Knobs.”

“Yes, the Three Knobs,” chief hair designer Lisa Tomblin told PEOPLE about the new hairstyle for Rey (Daisy Ridley). “We just joked because everything was so secret and we used to have code names, including Rey’s hairstyle. I was trying to do something that would again be iconic, simple, realistic, but not overdone.”

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Complementing that utilitarian hairstyle was desert-style makeup, or lack thereof. “When we find Rey in the desert, she’s a scavenger, and [director] J.J. Abrams said, ‘I really don’t want to see her with amazing makeup or anything. She’s gotta look like she lived there and be dirty and be sweaty,’ ” recalls Amanda Knight, head of the makeup department. “[Daisy] has a spray tan every day to make her look like she was living in that environment.”

Carrie Fisher, now playing Princess-turned-General Leia, appears to have a more conservative hairstyle at first. “That’s the way J.J. wanted to go with it,” Tomblin says. “It keeps her very in with all the other rebels and then … BAM! At the end, you suddenly see the sort of iconic Princess Leia look.”

Expect more throwback style to the original trilogy rather than the prequel Episodes I-III, at least when it comes to the makeup. Princess Leia’s mother, Queen Amidala (Natalie Portman), was especially heavy on the makeup in Episode I.

“J.J. was very much for making characters look real,” Knight says. “In some of the other Star Wars, there was a certain kabuki feel with a lot of makeup going on, which sometimes drew your attention away from the story and the characters. J.J. wanted real characters, real people who actually looked like they were living in the world that you found them in.”