When preparing for the ethics paper in UPSC, candidates should focus on understanding the fundamental principles of integrity, transparency, and accountability in governance. It's crucial to analyze case studies that exemplify ethical dilemmas faced by public servants. Self-reflection on personal values and practices can help in articulating one's ethical framework. Familiarizing oneself with the Gandhian principles and various philosophical texts on ethics can provide deeper insights. Practicing answer writing within a time limit is vital for developing clarity and conciseness, crucial for effective communication during the exam.