Hello Gopal.
First of all develop a set of skills required for the job or profession you want to enter along with your studies in the college itself. If your college has good on-campus placements, it's great. Incase you want to go through the off-campus route, make sure that you do register yourself at the various jobs portal online and keep a track of 'Careers' section of the websites of companies or firms you wish to join. Do keep your resume updated as you might be required to send it immediately to the firms.
I hope this would help.