Common pitfalls to avoid while preparing for the UPSC Civil Services Examination include overloading study material without a strategic plan, neglecting current affairs, and failing to practice answer-writing. Candidates often underestimate the importance of revising earlier topics, leading to gaps in understanding. Disregarding time management during both preparation and the exam itself can be detrimental. Moreover, avoiding burnout through consistent breaks, as well as maintaining a healthy balance of study and relaxation, is critical for sustaining productivity and focus throughout the preparation period.