This document provides an introduction to design thinking and how to build the right product. It discusses common mistakes like making wrong assumptions, missing context of use, and poor execution. It then outlines the design thinking process which involves empathizing with users by understanding their perspectives without assumptions, defining the problem and constraints, ideating creative solutions, prototyping ideas, and testing prototypes with users. Finally, it provides an overview of design methodologies like Lean UX, Agile UX, and Design Sprints and recommends tools to use at each stage.