Have you gone through the past paper thoroughly to see where you are making mistakes. If you find that you always mess up on the integration questions, for example, perhaps do a few questions from that section of the textbook. You may want to try some practice questions from a revision workbook as well. If you find that the main cause of mistakes is not reading the questions properly so you are losing silly marks for giving your answer in degrees rather than radians; or not working out the other root of a quadratic equation; or not finding all the values for theta between 0 and 360, giving only the first answer that appears on your calculator etc. then you need to work on your exam technique and so past papers are the way to go.
Try to aim to get all/ most of the past papers available done by a few days before your exam, so a paper every other night seems perfectly acceptable. But yes, make sure you revise other subjects too!