This document provides an introduction to building virtual reality display systems for hobbyists and educators. It discusses the history and applications of VR, key engineering challenges in the field, and gives an overview of the Stanford EE 267 course where students build their own VR head-mounted displays. The document covers topics such as the graphics pipeline, sensor fusion for tracking, and spatial sound. It also profiles the open-source VRduino hardware platform used in the course for orientation tracking, input interfacing, and more. Overall, the document serves as a guide for those interested in developing VR technology through a do-it-yourself approach.