This document provides guidance on testing paper prototypes early in the design process. It outlines common activities for research, design, and evaluation such as creating personas, scenarios, and wireframes. For testing paper prototypes, it recommends specifying clear tasks without solutions, asking open-ended questions, and preparing by writing a script. The roles of facilitator, participant, observer, and "wizard of oz" are described. Tips for conducting the test such as thinking aloud and taking notes are provided. The document concludes with recommendations for reflection on test results and design changes.