Transmedia storytelling has the potential to be an effective approach for non-formal education. Previous research has suggested that there may be a reciprocal relationship between transmedia storytelling and the characteristics of non-formal learners. However, there is limited literature on how to structure and design educational processes using this approach in non-formal settings, and even less literature that integrates the perspectives of stakeholders on the necessary components for instructional design. To address this gap, a qualitative analysis of multiformat focus groups was conducted to describe the necessary items to be considered when developing transmedia educational process (TEP) in non-formal educational proposals when these are designed to families, children, and/or adolescents. Based on the findings, seven important levels were identified for instructional designing of TEPs: level of intentions (1), level of facilitators’ indications (2), level of participants’ needs (3), level of narrative integrations (4), level of elaboration and production (5), level of means and technological/physical support (6), and level of sharing willingness (7). The study discusses the importance to consider multiple perspectives, including those of facilitators, children and adolescents, and parents, when designing TEPs. Additionally, it is important to use a variety of media platforms, formats, and channels to engage diverse and heterogeneous groups of participants in non-formal educational settings. Further research could focus on developing and validating tools and strategies to guide instructional design in these types of educational processes.