Explore the intricacies of monitoring large-scale systems and designing intuitive dashboards in this 47-minute conference talk from PHP UK Conference 2013. Delve into the challenges of processing millions of events per second and learn how to effectively evaluate system health without overwhelming infrastructure or personnel. Discover cognitive science principles for efficient information processing and decision-making. Gain insights on collecting useful metrics, organizing data, and creating optimal monitoring dashboards that leverage intuition and reduce mental effort. Topics covered include fast thinking, infographics, brain fatigue, information organization, embellishments, cognitive biases, instrumentation, distribution, and heat maps. Access accompanying slides for visual reference and enhanced understanding of the concepts presented.