One of the main barriers to the actual shift to open science is that most people, even within the open science community, operate in separate silos. In order to overcome this, we need other formats than presentations and panels. Open Science Cafes do have the potential to connect different stakeholders, as they facilitate listening and sharing thoughts. In short, it consists of roundtable conversations that are ignited by statements on a set of cards. This manual is part of the kit Organise your own Open Science Cafe.