The essential components of effective note-taking for UPSC preparation include organization, clarity, and revision. Aspiring candidates should adopt a structured format, such as the Cornell method, to facilitate easier review. Incorporating diagrams and charts can also enhance understanding and retention. It's crucial to summarize information in one's own words and regularly revisit notes for effective revision. Utilizing technology, like note-taking apps, can streamline the process and keep notes accessible. Additionally, personalizing notes according to individual learning styles significantly boosts engagement and memory during preparation.