while you prepare for CSS you are not a blank sheet.you have lot of experiences of your life,educational background and experience of attempting several exams from class 1.on other hand css is not the exam of just cpmlusory+optional subjects.it is test of your nerves,it is test of your time management, it is test of your personal thoughts.in this regard the time period of 8 month is enough for any person to pass this exam.all you need is to ORGANISE 1) your time 2) your thoughts and 3) studies.