Here are some general guidelines:
* In a formal essay or research paper: You should not italicize lyrics unless you are quoting them directly and they are more than three lines.
* In informal writing: It is generally not necessary to italicize song lyrics.
* If you are directly quoting lyrics: You should italicize the lyrics if they are more than three lines. If they are three lines or less, you can use quotation marks.
* If you are referencing a song title: You should italicize the title.
Example:
* "The song's lyrics, *'She's got the look,'* are iconic."
* "The song *'Bohemian Rhapsody'* is a masterpiece."
Ultimately, it's up to you to decide how to format your writing based on the context and your intended audience. Just be consistent and clear in your choices.