Believe it or not, Taylor Swift Style: Fashion Through the Eras author Sarah Chapelle predicted a song title on The Tortured Poets Department . Chapelle, who’s studied Swift ’s fashion choices for 13 years, exclusively opened up to Us Weekly about analyzing the pop star’s outfits and hunting for Easter eggs while promoting her upcoming book, Taylor Swift Style , available on Tuesday, October 8. “Having done it for as long as I have, you start to pick up really small details,” Chapelle explained to Us , noting she’s able to find every garment Swift, 34, wears because she’s “aware of the brands” the singer gravitates toward.

“It’s just come down to a lot of hard work and a lot of research. I feel uniquely qualified to be this expert source on her style evolution.” Chapelle, who also created the Instagram account @TaylorSwiftStyled to break down Swift’s outfits, added that no matter how Swift “evolves” her style to “cater to each of her different eras ,” the Grammy winner always stays true to herself.

“It’s still very recognizable and very signature her,” she explained. According to Chapelle, Swift has “a very traditionally feminine” sense of style as well as “a certain level of quirkiness or relatability” to her wardrobe. From flowy frocks and sparkly outfits to skirts and baseball caps, Swift often dresses casually while out and about.

The singer is also known to put her own twist on outfits, wearing skirts and tops backwards. La.