Start with the basics like building the conceptual understanding especially in case of Quantitative Aptitude and Reasoning, in case of PO the pattern of question is of very high level, almost to management exams, Clerk is comparatively easier, go through standard books, practice mock papers, evaluate your progress on a daily basis, have a good and positive mindset, and for CET being the sole gateway for government exams, as different exams have different patterns in the sense of we talk about weightage, perhaps the core areas of Quantitative Aptitude, Reasoning, English, General Awareness more or less remain the same, but we need to wait for official notification regarding this matter for full clarity on this issue.