Programming Languages

The answer below is a little tailored towards campus placements and my selection in Google. In case of off campus placements, the process remains the same, but you just have to make sure that you get that interview call. And you can expect the number of interviews to be more.
Getting a job in a good product based company can be tough. The recruitment procedure is thorough and grueling. In my experience resumes don't play a very important role beyond the function of getting the first interview call. Even in that the resume is mostly used as a rejection criteria rather than acceptance criteria.
In reality nobody cares if you organized the technical fest, headed the Cultural Council, were the sponsorship lead, because at the end of the day they want you to write awesome code. Often the only thing that they ask from your resume is to describe your favorite project, which too mostly is an ice breaker. If you want to get a job in a good software firm, learn to code and that too code well. And not only code you must learn how to develop things. Contributing to an open source project and working on algorithms and data structures is important.
A good book for Algorithms is “Algorithms” by Sanjoy Dasgupta
Data Structures and Algorithms in C+ by Adam Drozdek
Practice at least 50 interview questions for which company you are appearing for from sites such as
MyCareerStack
GeeksforGeeks
CareerCup
The best way to get selected is to practice loads of interview questions for the company that you are appearing, and not only solving them but also learning them. You should also watch MIT Online Course videos at ocw.mit.edu/courses
Coming onto things more specific to the placement time. Placement season can be a tough time, especially since you have to appear for so many written tests, listen to ppts (that hardly help) and then prepare for interviews. However it gets more stressful when you see others getting placed and you losing out, sometimes out of sheer bad luck. The right thing to do is to maintain your nerve and understand that luck also plays an important part.
However one of the most important things for interviews is that you should learn how to represent your knowledge accurately and confidently. You may know a lot of things but it is of no use if the interviewer does not get to know that. So you must be confident and clear in your answers and try not to fumble up things. Panic attack is a very common thing during an interview and it generally happens if you