On the basis of the experience of a community of practitioners, experts, engineers involved in the development of the EPOS Research Infrastructure, now with the ERIC status, involved in the ENVRI cluster and participating to the ENVRI-FAIR initiative, a common approach was observed, which is reflected into the re-organization FAIR principles into a four-stages roadmap which include: a) data stage, b) metadata stage, c) access stage and d) use stage. These stages correspond to the actual conceptual approach driving day-to-day work of RI implementers in the solid Earth domain (EPOS). Data are usually the main business and wealth of scientists and data practitioners in RIs. As a consequence, the first conceptual step relates to data aspects (Stage 1). Once data is properly managed, RIs professional tend to conceptually tackle the challenge of data description and identification, in order to create the premises for data searchability and contextualization (Stage 2). Once data is properly managed, described and contextualized by means of metadata, then RIs practitioners approach the issue of making it accessible to users (Stage 3). In order to include functionalities that go beyond data access, for instance data analysis and processing, FAIR RIs and data stewardship systems should address a fourth stage concerned with services that make use of data (Stage 1) and metadata (Stage 2) FAIRly accessed (Stage 3) and produce new (meta)data as output.