Cook up and Play it by ear

Cook up verb - To create or think of by clever use of the imagination.

Play it by ear and cook up are semantically related. In some cases you can use "Play it by ear" instead a verb "Cook up".

Play it by ear verb - Decide on one's actions as one goes along, depending on the situation.

Cook up and play it by ear are semantically related. Sometimes you can use "Cook up" instead a verb phrase "Play it by ear".