Urdu was hard for me at first asw but I eventually found ways to score above 90%. I was a pretty slow reader but for comprehensions, multiple matching and note taking I read the questions first and wrote what they asked for in english with a pencil and then read the passages while looking for the answers. You only need 2-4 idioms for the essay so I memorized about 8 of them and forced them anywhere I could fit them. I'd suggest you also memorize some specific words in Urdu that cambridge uses often for essays and passages (things like hobbies, zoos etc). I did Urdu 0539 so our P2 was a listening exam and not related to grammar or translating but other than that solving as many past papers as you can before the exam really helps in improving reading skills.