This book explores how to compose sounds and visualisations that represent psychedelic hallucinations and experiences of synaesthesia. Through a detailed discussion regarding compositional methodologies and technical approaches, the book aims to educate students, practitioners, and researchers working in related areas. It weaves together sound, visual design, and code across a range of media, providing conceptual approaches, theoretical insights, and practical strategies, which unlock new design frameworks for composing psychedelic sounds and visualisations.