Mental exercises that improve focus during UPSC preparation include mindfulness meditation and cognitive exercises. Practices such as deep breathing can reduce anxiety, enhancing concentration and facilitating better information retention. Additionally, engaging in puzzles or brain games can sharpen mental agility and stamina. Establishing a consistent daily routine incorporating short breaks can prevent burnout and maintain productivity. Techniques like the Pomodoro Technique encourage focused study sessions interspersed with short rests, which helps maintain attention. By fostering a disciplined study habit and incorporating these exercises, candidates can significantly improve their cognitive performance during extensive preparation.