Citizen science empowers public participation and trust in research, but successful projects depend on strategic recruitment and sustained community engagement that again depend on available training of Open Science skills. Developed within the EU-funded PATTERN project (Piloting Open and Responsible Activities and Trainings Towards the Enhancement of Researchers Networks), our training module addresses these challenges. PATTERN promotes Open and Responsible Research and Innovation (OpenRRI) through eight training themes, each enhancing transferable skills critical for researchers' professional growth, as outlined in the Salzburg II Recommendations by the European Universities Association. The “Participant Recruitment & Community Engagement in Citizen Science” training module is designed to prepare researchers and coordinators with practical skills and ethical guidance to foster effective public involvement. Building on our comprehensive analysis of existing OpenRRI training resources, it addresses gaps and identifies best practices. Based on a project-based and interactive approach, key elements include: Understanding Participant Motivations: Identifying the values, interests, and knowledge goals that drive citizens to engage in research activities. Ethical Considerations: Exploring ethical principles for inclusive and responsible research participation. Strategic Recruitment Techniques: Developing approaches to reach diverse audiences, including underrepresented groups. Sustaining Engagement: Implementing strategies for continuous participant involvement, feedback mechanisms, and community-building. Our poster will showcase insights from pilot implementation of the module. Pilots are designed to provide insights into the effectiveness and possible improvements of the module in enhancing participant recruitment and community engagement practices.