Strategies for effective public speaking in UPSC interviews include maintaining eye contact with the panel, using a clear and confident voice, and being well-prepared on multiple topics. Aspiring candidates should practice mock interviews to build confidence and receive constructive feedback. Organizing thoughts logically, making relevant analogies, and showcasing knowledge of current affairs can enhance the impression. Additionally, maintaining a positive body language, demonstrating enthusiasm, and handling difficult questions gracefully are essential for impactful communication.