This document summarizes the key lessons from the EUDAT Summer School 2017, including an overview of Horizon 2020 data management plan requirements, the FAIR guiding principles for data, the importance of metadata and ontologies, services from EUDAT and others for storing, managing, preserving and sharing research data, how to select appropriate data repositories, and how to calculate research data management costs. It encourages participants to complete a FAIR checklist for existing data, consider how FAIR their future data can be based on what they learned, and identify the most challenging aspects of making data FAIR.