Effective revision after completing the UPSC syllabus involves a structured approach. First, create a revision timetable that prioritizes critical topics based on their weight in the exam. Utilize previous years' question papers to identify recurring themes and focus areas. Engage in regular self-assessment through mock tests to track progress and pinpoint areas needing improvement. Form study groups for collaborative learning and discussion, which can enhance retention and understanding. Lastly, revisit key concepts regularly to reinforce knowledge, ensuring you remain well-equipped for the examination.