The EU Mission ‘Restore our Ocean and Waters’ (hereafter Mission Ocean and Waters) aims to protect and restore the health of our ocean and waters through research and innovation, citizen engagement and blue investments. It supports regional cooperation through four regional lighthouses acting as pilot sites to demonstrate and implement Mission activities in the Atlantic-Arctic, Mediterranean Sea, Baltic-North Sea, and Danube-Black Sea. These lighthouses act as piloting sites to demonstrate and deploy mission activities. The Prep4Blue project aims to support the deployment of the Mission Ocean and Waters by setting the foundations for its implementation in its first phase (2022-2025). It has developed concrete outputs such as communication tools, guidelines and methodologies to be used by Mission funded projects and stakeholders to achieve the Mission’s objectives. The Mission Ocean and Waters national hubs serve as collaborative platforms designed to implement the objectives of the EU Mission Ocean and Waters. This guidance document aims to guide EU Member States in setting up a national hub for the Mission Ocean and Waters.