In the design process, designers make a wide variety of decisions that are essential to transform a design from a conceptual idea into a concrete solution. Recording and tracking design decisions, a first step to capturing the rationale of the design process, are tasks that until now are considered as cumbersome and too constraining. We used a holistic approach to design, deploy, and verify decision cards; a low threshold tool to capture, externalize, and contextualize design decisions during early stages of the design process. We evaluated the usefulness and validity of decision cards with both novice and expert designers. Our exploration results in valuable insights into how such decision cards are used, into the type of information that practitioners document as design decisions, and highlight the properties that make a recorded decision useful for supporting awareness and traceability on the design process.