This document provides guidance on designing effective data visualizations. It discusses the main types of charts and graphs including bar charts, pie charts, line charts, area charts, scatter plots, bubble charts and heat maps. For each type, it describes best practices for design, such as starting the y-axis at 0, using consistent colors, and limiting the number of data series shown. The goal is to help readers understand their data and tell their intended story through clear, impactful visual representations.