Preparing for the Engineering Drawing section in the Mechanical Engineering optional subject requires a systematic approach and thorough understanding of the subject matter. Here are some specific tips to help you prepare effectively:

1. Understand the Syllabus:
- Familiarize yourself with the syllabus provided by the UPSC for the Engineering Drawing section. This will help you identify the topics that need to be covered and prioritize your study accordingly.

2. Study the Basics:
- Start by revising the fundamental concepts of Engineering Drawing, including orthographic projections, isometric projections, dimensioning, sectional views, and various types of lines and symbols used in drawings.
- Understand the principles of drawing conventions, scales, and limits, as they form the basis for creating accurate and standardized engineering drawings.

3. Practice Drawing Techniques:
- Regularly practice drawing different types of projections, such as orthographic, isometric, and auxiliary views. Pay attention to the correct placement of lines, proportions, and accurate representation of dimensions.
- Practice creating sectional views and understand how to interpret them.
- Work on freehand sketching to improve your visualization and drawing skills.

4. Solve Previous Year Question Papers:
- Solve previous year question papers to get acquainted with the pattern and type of questions asked in the exam. This will give you an idea of the level of difficulty and help you identify areas that require more focus.
- Analyze your performance and identify any recurring topics or types of questions that you find challenging. Allocate more time to practice these areas.

5. Refer to Standard Textbooks:
- Refer to standard textbooks on Engineering Drawing to gain an in-depth understanding of the subject. Some recommended textbooks include "Engineering Drawing" by N.D. Bhatt and "A Textbook of Engineering Drawing" by R.K. Dhawan.
- Use these textbooks as reference guides to clarify any doubts or concepts that may not be clear from your regular study materials.

6. Join Online Discussion Forums:
- Join online discussion forums or communities where you can interact with fellow aspirants and experts in the field. This will provide an opportunity to discuss doubts, exchange study materials, and gain additional insights into the subject.

7. Take Mock Tests:
- Take mock tests regularly to simulate the exam environment and assess your preparation level. This will help you manage time effectively during the actual exam and identify areas where you need improvement.

Remember, consistent practice and a thorough understanding of the subject are the key to excel in the Engineering Drawing section. Stay focused, manage your time wisely, and stay updated with any changes in the syllabus or exam pattern. All the best for your preparation!