Last year I was in NIT Durgapur and the campus placement started at the month of July. There were many good companies that came to our campus for recruiting. All the students tried their best to get into those companies so the competition was very tough among the students. Also, there were some students who have another dilemma either they should prepare for Campus Placement or they should prepare for CAT.
Not preparing for Campus Placement means you take high risk with your career. It will be also frustrating for you when you will see that your friends will get a job one of the best companies and you won't. This frustration will start to affect your personal life and it may start to affect your studies.
Also, not preparing for CAT means that you that you leave your dream which you have for the last 2 or 3 years. If you don't continue your preparation for CAT you will find yourself at a position which will demotivate you for taking the CAT.
Now in this situation what is the best course of actions that you can take? From my point of view, you should continue with both of the preparations simultaneously. Also, you need to try to manage at least one hour for news paper reading. Most of the companies which will come to your campus will conduct Aptitude Test for their selection procedure. CAT preparation will help you most at this point. If your concepts about the QA, DI & LR and VA section of CAT are crystal clear no one can stop you to clear the Aptitude Tests of these companies. I cleared each and every Aptitude Test of the companies of my Campus Placement.
Also, some companies will conduct GD for their recruiting procedure. To perform well in GD round you need good information about recent affairs and you will get that information with effective newspaper reading. Whatever information you will get from this newspaper reading try to maintain a summary that information because after getting calls from IIM, that information will be very helpful for your WAT (Written Ability Test) preparation and also for the preparation for your personal interview. Also if you want to take XAT or IIFT, it will be also helpful for clearing the GK sections of that exams.
CAT preparation does not end with scoring a good percentile in CAT, you need a decent academic background for further process. So don't forget to prepare for your college study. It will also help you in the Campus Placement as well as the personal interview of various IIMs. In most of the IIM's interviews, I realised that most of the questions came from my departmental subjects. So it is better to study the Final year subjects as well as the previous year subjects. It will also help you in your Campus Placements.
So how to manage time for all of these?
It is a very simple plan :
1. Read the newspaper for at least one hour.
2. Try to take mock tests one for every two days. After taking the mock test check for which type of questions you face difficulties. Try to analyse that questions and try to solve the similar type of questions.
3. For DI-LR section try to solve as much as questions you can after the day on which you take the mock test.
4. Try to solve 4-5 RC passages and 5-6 VA questions every day.
5. Solve 15-20 QA questions on various topics per day.
6. Study your departmental subjects thrice a week.
This was the plan for my success and it worked really good for me. I think as I followed this plan, now I am in IIM Rohtak.
As an engineering student I think you go to bed very late at night, so try to utilise that time for your studying.