Aspirants can maintain sustainable motivation throughout their UPSC preparation by setting clear and achievable goals. Creating a structured study timetable with small milestones can help in tracking progress. Regular breaks and self-rewards for tasks completed keep the motivation levels high. Engaging with fellow aspirants through study groups can foster a sense of community and provide mutual support. Additionally, maintaining a balanced lifestyle that includes exercise, proper nutrition, and leisure activities contributes positively to mental health, ensuring sustained motivation.