To boost confidence before the UPSC interview, aspirants can adopt several strategies. First, engaging in mock interviews with peers or mentors helps familiarize them with typical questions. Practicing articulation of thoughts and body language reduces nervousness. Additionally, thorough research and preparation regarding current affairs can instill confidence in discussions. Visualizing success through positive affirmations is another technique to enhance self-belief. Finally, maintaining a regular routine, including exercise and relaxation practices like meditation, aids in managing stress effectively.