Aspirants enhance their writing skills for the UPSC Mains exam by engaging in regular practice and seeking feedback. Writing daily essays and answers on various topics helps improve structure, coherence, and clarity. Joining study groups or coaching institutes for peer review often provides constructive criticism. Familiarity with the exam pattern and practicing previous years' questions can further assist in aligning writing style with expectations. Additionally, reading quality essays and understanding effective argumentation techniques contribute to enhancing overall writing proficiency, essential for success in the Mains.