For NDA exam preparations, the student should solve previous years question papers/model question papers daily. The previous question papers and mock tests will help you to get familiar with the syllabus, weightage of question and exam pattern. It will also give you information about the difficulty level of the question paper and which type of question can save them more time. With the help of NCERT and previous years question papers, you can ace NDA exam easily. Check the previous year's question papers (PDF format).