by the book

idiomatic broadly

(idiomatic) In a manner which adheres strictly to rules, legal requirements, or official procedures.

Japanese Meaning

規則や法的要件、公式な手続きに厳格に従って行動するさま、すなわち「定められた手順に沿って」や「マニュアル通りに」を意味する

When conducting the audit, she insisted on doing everything by the book to avoid any legal issues.

監査を行う際、彼女は法的な問題を避けるために、すべてを規則に厳格に従って行うことを主張した。

Sense（1）

(idiomatic) In a manner which adheres strictly to rules, legal requirements, or official procedures.

As far as he is concerned, he umpired by the book.

Sense（2）

(idiomatic, by extension) In a manner which appears too studied, ritualized, and therefore artificial.

Romeo: Sin from thy lips? O trespass sweetly urged!

Give me my sin again.

They kiss again.

Juliet: You kiss by th' book.