CSS is impossible with job unless you have given one attempt with full-time preparation. After first chance, you can take rest of the chances with a job. Even then, it would be very difficult because inevitably student syndrome will keep you away from book till last few months. Last few months of full-trme preparation would be needed in 2nd and 3rd chances. I gave CSS last year with full preparation and scored reasonable marks failing in precise. This year when I sat down to prepare, I realized that I had forgotten everything and had to start from scratch. In sum, if you want to give CSS with job, you will have no respite. As soon as you get back home, you will have to start studying. You will have to devote as much time in a full year as aspirant preparing full-time gives in last few months.

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There is no one to stop you from succeeding other than yourself