Effective habits for long-term retention of UPSC study material include techniques like active recall, spaced repetition, and self-assessment. Engaging with the material through quizzes and practice tests reinforces memory retention. Creating summarized notes and visual aids can also help in consolidating information. Studying in intervals rather than cramming offers better retention, as the brain processes information more efficiently over time. Finally, maintaining a consistent study schedule and taking regular breaks can enhance focus and cognitive function.