Many people living with dementia are 'on the margins', not accessing services and support, despite policy and care advancements. The COVID-19 pandemic exacerbated this, with the closure of face-to-face support during lockdowns in the UK and globally. The aim of the 'Beyond the Margins' project was to develop, implement, and evaluate a face-face programme of support with, by and for people with direct experience of dementia who are on the margins of existing services and support. In March 2020 the project was interrupted by the outbreak of the COVID-19 pandemic and it changed to an online format. The three-phase participatory action research project included 40 people living with dementia, 26 care partners and 31 health and social care practitioners. A seven-week online personal development programme called Getting On with Life (GO) was developed, delivered, and evaluated. This paper focuses on the participatory approaches used to develop and implement the GO programme, and the resulting aspects of its approach to facilitation and content. Key features include the GO Programme's principles of providing a safe and a respectful space, and the programme's values of: Everyone who comes already knows things, can learn things and can teach things; Doing things 'with' each other, rather than 'for' or 'to' each other; Personalised goals-led by the needs of participants rather than an imposed agenda. A key finding was the importance of developing post-diagnostic programmes as a 'sandwich', providing a safe space for learning that is preceded by understanding pathways to access the programme and followed by explicit consideration of the next steps in increasing social engagement.