INTRODUCTION: Public involvement in research improves its relevance and accessibility to ensure it reflects the population it serves. However, there is a lack of information about how patients and the public are involved in shaping systematic reviews. There is also a need to address the lack of diversity in public involvement, particularly around the inclusion of underserved communities. This paper outlines the practical approaches taken to involve a diverse group of public contributors in a systematic review process and offers recommendations to support future practices. METHODS: This paper uses the ACTIVE framework developed by Pollock et al. (2019) to structure our reflections on public involvement in an NIHR-funded systematic review project on the effectiveness of interventions used to increase vaccination uptake. RESULTS: We present the practical approaches used to recruit and engage a diverse group of public contributors in a systematic review project. They had continuous, hands-on involvement in various aspects of the systematic review process. Our approach enabled the public involvement group to play an integral role in adapting and refining a coding framework, contributing to the development and refining of codes and categories used for the analysis. DISCUSSION: Our paper highlights the importance of involving public contributors who have a range of experiences and backgrounds in the systematic review process. By investing time in relationship-building, creating a safe environment and recruiting a diverse group of contributors, we gained richer insights that enhanced the coding framework. The complexity and nature of the methodology could make it challenging to identify where public contributors can make a real difference to research. Our experiences demonstrate that such involvement is possible and generates mutual benefits, including research that is better designed to reflect the diversity of the population. CONCLUSION: This paper outlines the steps undertaken to involve public contributors in the systematic review process. Key suggestions include investing time to build relationships, providing ongoing feedback, incorporating creative activities and developing strategies for disseminating research findings to wider audiences. These recommendations build on existing guidance and aim to support researchers in effectively involving public contributors in the systematic review process. PATIENT OR PUBLIC CONTRIBUTION: All public contributors working on the vaccination uptake project have been involved in reviewing this paper. Two public contributors P.D. and B.D. are also co-authors and have provided input to the writing and review of this manuscript.