Metaverse, the concept of a persistent, virtual space shared by users worldwide, has garnered enormous attention among scholars, technologists, and business leaders. However, effectively designing and deploying Metaverse use cases requires a comprehensive framework incorporating multiple dimensions. Unfortunately, existing methodologies typically focus only on technology and operational aspects. This paper introduces the LETO methodology. It provides a holistic view to ensure solutions are compliant, sustainable, and operationally efficient, addressing the legal, ethical (including environmental and social), technological, and operational dimensions. The paper demonstrates how LETO can help stakeholders navigate the complexity of Metaverse through the WineMetaverse Platform, a blockchain-based pilot project enhancing the wine purchasing experience. Furthermore, benefits, limitations, and future research directions of the LETO are discussed.