Well, the answer sheet provided is almost same as that provided in HSSC or SSC examinations. But the quality of paper is not good. So I would recommend not to use pointer pens or markers. Instead, use good quality ball point pens. There are no lines on the answer sheets, so need to be more careful while writing. You should try to write in straight, parallel lines. A little ascending lines are acceptable but lines going downwards is not acceptable, so watch out & start practising on plain A4 paper from now to avoid any surprise in the exam hall.