The process is as follows.
1) Online test.
2) Online essay writing.
3) Technical interview.
4) HR interview.
Online test consists of 170 questions and you have to complete them in 80 minutes.There is no negative marking. These 170 questions are divided into 7 modules and there is sectional cutoff. Out of these 7 modules, 3 modules contain questions related to English and they are easy( not very easy, you have to prepare a bit). 1 module of quantitative aptitude. 3 modules consisting of questions related to reasoning.
English--- 100 marks
Quantitative aptitude---15 or 20 marks
Reasoning---- around 50 questions
The proportion of marks may vary!!! For English, you have to know the basic grammatical rules, because most of the questions will be testing you on that part. And apart from that the topics you should stress are 1) Synonyms 2) Antonyms 3) Analogies and take a look at Prepositions , Articles and Tenses. First make sure that you know the basic rules of English. That's enough. We can anyway answer the reading comprehension easily. But be careful, understand the passage clearly and then answer the questions. Nothing will be very easy and you have to concentrate a bit.
For quantitative aptitude, R.S.Aggarwal book is more than enough. 15-20 questions will appear in quantitative aptitude section. The questions will be from Partnerships, Simple and compound interest, Profit and loss, Percentages, Time and work etc. 3 modules are from Reasoning part. For this you should practice Blood relations, Directions, Series completion, Odd man out, Figures and some other logical questions. There is sectional cut off friends. So be careful. Don't neglect any part. There is no negative marking. So answer all the questions. Manage the time wisely. We are not informed with cut off percentage for written test!!! If you clear the written test, then you are asked to continue to the essay writing section. The time is 10 minutes and you have to write 150-200 words on the topic given to you. If you make more than 5 mistakes ( Grammatical and spelling mistakes combined ) , you are eliminated.So be careful. Just be calm and write it in simple English. You can easily crack the essay writing part. The only thing you have to do is don't panic and use simple words. Don't search for some extra-ordinary words. If you clear the essay writing, then you will be qualified for further rounds. Remember guys, there is elimination in essay writing also. Be confident and prepare well. Don't be so bothered about the sectional cut off ans essay writing. It just needs a bit of preparation and it is easy to crack.