This manual is part of a kit produced within an extracurricular programme on HIV & AIDS education using the peer education method. It is intended for all specialists working with young people: teachers, social workers, students, etc. The aim of this manual is to prepare young people aged 14-19 for voluntary work in the field of HIV & AIDS prevention among their peers. It is divided into five chapters: 1) "Prevention activities. Ideology, content and methods of peer education", 2) "Preparation of the volunteers: from choice to action", 3) "Preparation towards the delivery of lessons" 4) "Content of the lessons for volunteers preparation" and 5) "Trainer's toolkit". The first two chapters provide theoretical and methodological information related to prevention work, peer education and the preparation of volunteers. The last three chapters are dedicated to practice and contain basic information on HIV & AIDS and methodological advice on the preparation and delivery of lessons. The last chapter presents a wide range of interactive activities that can be used among the volunteers to cover different HIV & AIDS-related topics. Some activities can be used by the volunteers during outreach sessions with their peers. The appendices contain a quiz to assess knowledge of the volunteers, a collection of useful links and a glossary.