It is possible to make it even in 3 months, but you have to make a plan and try to follow it.


....... First identify ur skills and what is the motivation for opting CSS. If you will decide for these things then make a plan of study. First plan your work then work your plan.


....... Second check yourself according to some defined criteria like how much words you can write for an unknown topic if its given to you, or what information you have about your surroundings. All these information will help you to organize a workable plan.


....... If you r good in reading make it habit to read more and more and if you r good in writing make plan to write atleast 200 words at daily basis but make it time bounded. And in the case if you r not good in both skills then practice them more and more.


...... If you r expressive its very good if you r not expressive then read an article of the paper daily... and then reproduce it in your own words. It will help you to make your expression perfect.


....... There is no shame if you have vocab problem but its the real shame if you will make wrong choices in your papers. Words have their place and they should be used according to the context. Every word has different intensity and frequency so it should be used according to it. So try to learn the usage of vocab according to the context. There are words used for negative context and some for positive context but a naive to the language may use positive word in negative sense and negative words in positive sense. So be careful for the usage of words.


....... Final is the suggestion to make yourself perfect in english language from all the corners and make your expression a pleasure for its reader. It will score marks for you not only in English but also in other subjects.


Now after going through above points you can take decision that can you prepare for it within 18 months or not. I m not agreed to a person if he/she is saying that you can prepare for CSS in 6 months... or 18 months... or 3 months its basically about the skills you already possess. If you have grasp of different field of studies then you can make it in little time but if you dont have the grasp may be 3 years are insufficient.

On the other hand there is no surity to qualify the exam after studying by counting hrs. I m telling you my own experience that never count hrs... When I prepared for it, the whole day was mine.... hardly 4 hrs for sleep and meals time to time... it was the routine for one and half month and I scored 613 marks with failure of English Essay. So its not the matter of counting hrs rather its the matter of your planning and your skills. So I would like to suggest that sharpen your skills rather getting worried for the comments of your friends.

Regards

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"When Allah leads you to the edge of the cliff, Trust Him Fully, only 1 of 2 things will happen either He will catch you when you fall or He will teach you how to fly"