To summarize large amounts of information for UPSC, candidates can use techniques like mind mapping, which visually organizes information, and bullet points to condense essential data into digestible formats. Engaging in active reading by highlighting key points and using annotations can also streamline the process. Additionally, creating summaries after each chapter or topic helps reinforce learning and retain significant information. Utilizing flashcards for important facts and concepts can aid in quick revisions. These techniques enhance retention and retrieval, critical for success in UPSC exams.