This paper explores the persona-scenario method by investigating how the method can support project participants in generating shared understandings and design ideas. As persona-scenarios are stories we draw on narrative theory to define what a persona-scenario is and which narrative elements it should consist of. Based on an empirical study a key finding is that despite our inherent human ability to construct, tell, and interpret stories it is not easy to write and present a good, coherent, and design-oriented story without methodical support. The paper therefore contributes with guidelines that delineate a) what a design-oriented persona-scenario should consist of (product) and b) how to write it (procedure) in order to generate and validate as many, new, and shared understandings and design ideas as possible (purpose). The purpose of the guidelines is to facilitate the construction of persona-scenarios as good, coherent stories, which make sense to the storytellers and to the audience - and which therefore generate many, new, and shared understandings and design ideas.