Play by ear
Play by ear (English) — To play a musical instrument, the musical score from memory. To envision it in your head, sometimes with your inner voice singing the words and/or melody in your mind. . A good musician learns to play without looking at their fingers. This affords them the ability to maintain one focus of thought, not to focus on each individual musical note.
'Play it by ear' means to do something as it occurs without great forethought and planning. To just do things as they happen.
"Play by ear" in lyrics
Because you should've only the best of friends
One only, but reliable only the best of friends
Old, and truthful in trouble, only the best of friends
And I'm not going to play by ear
Surely everyone here knows who are the friend
And someone also calls you the best friend
And there's more than what you believe,
And there's more than what you can.
Don't play by ear 'cause I'm going to the other side,
and it brings the salty inside of me.
Don't convince me, I don't have patience anymore