Question

How to prepare for Placement activities through internet ?

Answer 1

It's very easy to start for the preparation for placements. Important is regularity. I suggest you to first work on the Aptitude tests i.e the first round for any company to pass, there are many online free websites that can provide quality apitude questions - questions related to profit/loss, time distance, percentage, number system, reasoning, english comprehensions , error detection etc are important topics. 

Other then appti test you should work for communication skills and learn your technical or course related subjects for the technical round. And the last is HR round, for this i suggest you to see http://www.indiabix.com/ site. Here you'll get the idea how questions are asked and how to answer them.

Answer 2

Before applying for any company first look at its site and explore it what the company is about and see company's placement sample papers so that you may get idea what all questions are asked and what is the level of aptitude test as all companies has its own aptitude test and different approach for questions.
Then technical you can prepare from varies Pdf files or can join few online courses that take practice test exams like Amcat, Indiabix.com, youth4work etc. For Hr round get prepared for questions like- Your introduction, Why company should hire you etc.