play it by ear
idiom

- proceed instinctively according to results and circumstances rather than according to rules or a plan

(Oxford English Dictionary)

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"None of us can read music. None of us can write it." (The Beatles' John Lennon, 1980) While this statement might astound some people, it's not uncommon to find rock and jazz musicians who don't or can't read music. Lennon's song-writing partner Paul McCartney didn't read music either, yet he became one of the most prolific composers in pop history.

Musicians like Lennon and McCarthy "play by ear", which means improvising without notes or listening to music and then playing it back based on what one hears. The expression "play it by ear" derives from this musical sense and is achieved by simply adding "it" to change the meaning to an impromptu decision.

Most rock guitarists don't bother with music notation. This can lead to the wrong result sometimes as guitar legend Jimi Hendrix pointed out: "I've been imitated so well I've heard people copy my mistakes."


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SYNONYMS

let's see what happens, take it as it comes, go with the flow

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SMUGGLE OWAD into today's conversation

"I often go on holiday without booking a hotel room and just play it by ear when I get to my destination."