As Nature-based Solutions (NbS) become a valid alternative to grey infrastructures (hard, human-engineered structures) for coping with climate-related risks in urban and rural areas, the increasing success of NBS is explained as due to their capacity to foster the functioning of ecosystems and to generate additional environmental, economic and social benefits that are considered as essential backbones of actions for climate change mitigation and adaptation. The depth and forms of citizen engagement in nature-based solutions (NbS), and how such participation shapes their trajectories is also gaining increasing attention due to the fact that most literature demonstrates that physical barriers are less important than those related to governance, socio-institutional and economic dimensions. The low level of social acceptance and the collaboration barriers come out as the critical influences in NbS implementations. Thus, the effectiveness of participatory modelling exercises in facilitating stakeholder engagement in NbS design and implementation has been shown to be a critical and viable approach for overcoming these barriers. The Report, after an introduction to the relevant best practices in the field, suggests Steps to the establishing of a Participatory Governance Plan or rather a Guide to the construction of a Plan that should take shape upon the realization of the participatory process at each case site where NbS will be implemented.