The phrase "makes it up as one goes along" can be used to describe someone who is improvising or winging it. Alternative expressions could include "flying by the seat of one's pants," "going with the flow," or "playing it by ear." Another synonym might be "ad-libbing," which refers to speaking or performing without preparation or a script. Similarly, "improvising" suggests creating something in the moment, often in response to unexpected circumstances. On the other hand, "spontaneity" describes the ability to act without planning or forethought. Regardless of the term used, these expressions convey a sense of flexibility, adaptability, and creativity in the face of uncertainty.