This document summarizes a training session for young Angolan entrepreneurs on testing business ideas to reduce risk and uncertainty. It discusses testing the desirability and viability of ideas through designing hypotheses, experiments, and metrics to gather evidence and insights. Key principles for testing include embracing failure to learn faster, understanding customers, and making tests measurable. Interview techniques are outlined to gain customer insights like acting as the customer. The training emphasizes testing early to refine ideas and prioritizing the most critical hypotheses first with cheap, quick tests before more elaborate tests.