Common resources recommended by successful UPSC candidates include standard textbooks, online courses, and aggregated material from various study platforms. Notable books covering the syllabus thoroughly are crucial, alongside current affairs magazines and newspapers for up-to-date information. Candidates often emphasize the importance of utilizing NCERT books for foundational concepts. Joining online communities can provide insights into the preparation methods of others. Some aspirants also recommend using coaching institutes or mentorship programs for structured guidance. Ultimately, tailoring resources to individual strengths and weaknesses is key for effective preparation.