Key techniques for effective writing in UPSC examinations include clarity, structure, and relevance. Candidates should start with a clear introduction outlining their main argument or information. Using headings and bullet points can enhance readability and organization, making it easier for evaluators to follow. Providing substantive examples and case studies is essential to substantiate claims and add depth. Time management is also crucial; practicing under timed conditions helps candidates develop concise responses. Lastly, staying relevant to the question prompt while maintaining a coherent flow throughout the answer enhances overall effectiveness.