Hackathons as events for participative, creative problem solving, originating from software development have been adapted to many other industries in recent years, among them museums. A series of hackathons was implemented in museums in different countries in the Baltic Sea region, in an international project uniting museums, universities and NGOs. This document summarizes the experiences made and lists the recommendations derived from reflections of the organizing teams of the four events. In this working paper, firstly, the project and the concept of hackathons is introduced. Then, the experiences made with different concepts for realizing hackathons for museums are described. Finally, the major part of this document describes the recommendations for developing a tailored hackathon concept, developing the event communication and planning the event infrastructure. The document additionally provides a template for a project plan and provides examples for gathering feedback after the event.