The whole process takes one complete day. There is generally a presentation(good 1) followed by written test which includes aptitude,reasoning,verbal and essay. The Written test is divided into three parts. The first part contains 15 aptitude questions,15 reasoning,15 basic computer related and 10 verbal questions. The second part has 5 minutes for reading comprehension. The third part is essay writing for 10 minutes. You should avoid any grammatical or spelling mistakes here. Questions are not very difficult but time is surely a factor. Try to be very accurate with your answers because very few are selected for written.
Out of some 600 odd students only 16 were selected. The next phase is interview. The main focus is on problem solving abilities and obviously basics of all the subjects. The second interview is generally taken by 2 people. One of them is a HR who asks very few questions but observes you very keenly. The other person is generally a senior guy and it will be just a little challenging.