This handbook describes the LIFE Agile Cocreation Methodology produced by the ACCRA Consortium for the development of socially assisted robots dedicated to the elderlies with a loss of autonomy, in the European H2020 program. The goal of the LIFE methodology is to bring together robotics developers, engineers, stakeholders and end-users to cocreate robotics solutions that are more meaningful to end-users, in particular on specific targets such as the elderly. The originality of this methodology is that it seeks to bring together two very different entities: robotics and the elderly with a loss of autonomy. The central axis of this agile cocreation methodology is to position the elderly user at the very heart of the development of robotic solutions.