* Read Instructions Carefully: Pay very close attention to the instructions given at the test center. They'll explain how to fill the sheet correctly. Any deviation from these instructions could invalidate your answers.
* Use a Black or Blue Ballpoint Pen: Never use a pencil or any other type of pen. The instructions will specify the correct type of pen. Use a pen that writes darkly and clearly.
* Fill Completely and Darkly: Fill the entire circle completely and darkly with the pen. Avoid going outside the circle. Partial or lightly filled circles might not be read correctly by the OMR scanner.
* One Answer Per Question: Select only one answer for each question. Filling multiple circles for a single question will usually invalidate that question.
* Cleanliness: Be careful not to smudge or make any stray marks on the answer sheet. Keep your hands clean to avoid soiling the sheet.
* Double Check: Before submitting your answer sheet, take time to thoroughly review your marked answers against your question paper. Look for any mistakes you've made and carefully correct them by completely erasing the incorrect mark and filling in the correct one. Complete erasure is crucial; a faint mark can be misinterpreted.
* Practice: Before the exam, familiarize yourself with the OMR sheet format by practicing on a sample sheet (if you can get one). This will help build confidence and improve efficiency during the exam.
In short: The key is accuracy and carefulness. Don't rush, follow the instructions precisely, and double-check your answers before submitting the sheet. The exam center instructions on the day of the test are the ultimate guide.