To approach interdisciplinary questions by integrating various subjects for UPSC, candidates should develop a comprehensive understanding of how different themes interlink. This involves recognizing overlaps between subjects like sociology, economics, and environmental studies. Techniques include creating mind maps or charts to visualize connections, which helps in structuring responses effectively. Regularly practicing interdisciplinary case studies enhances adaptability in thought processes, allowing aspirants to draw insights from multiple fields to formulate well-rounded answers in exams.