External feedback can be structured to improve essay writing for the UPSC exam by emphasizing clarity, coherence, and critical analysis. Constructive criticism should focus on content organization, relevance to the prompt, and argument strength. Peer reviews or mentorship from experienced aspirants can offer fresh perspectives and highlight areas needing improvement. Additionally, using criteria-based rubrics can provide a more systematic evaluation of essays, identifying strengths and weaknesses effectively. Incorporating this feedback into subsequent drafts fosters development and enhances overall writing skills, critical for success in the UPSC exam.