Effective note-taking methodologies for UPSC preparation include the Cornell Method, mind mapping, and using bullet points for clarity. The Cornell Method allows for organized notes, separating cues from main ideas, making review easier. Mind mapping visually connects various topics, enhancing comprehension and memory retention. Additionally, using bullet points ensures brevity while highlighting key concepts and facts. Aspirants should also regularly revisit and revise notes to reinforce learning. Integrating charts and diagrams can further aid understanding complex subjects, creating a comprehensive study resource for future reference.