You must understand the placement paper pattern before appearing for it.
The first hurdle to clear is the Written test in the placement paper. For example the Satyam computers company placement paper has like 55 objective type questions and the time allowed is 60 minutes. Thats just about a minute for a question. Then the next round for those selected in the satyam computers written test in the placement process is the GD or group discussion round. Its a difficult round. Just be confident and show your teamwork skills. Try to present good points and give a good conclusion at the end. Next you have the technical interview round. The questions may be tricky but you have to be careful about telling your favorite subject and also prepare your project well. This wil go a long way in letting you sail through the whole process.. Then comes the satyam computers hr interview round. You should write about your hobbies, favorites and other things carefully in your resume. Also just prepare the popular hr interview questions before the hr interview and answer them naturally. Work hard on these things and you may get a good job at your favorite IT company.