Vishalini,

Definitely, If you start right now then you can prepare in a relaxed manner.Spend some time going through the structure of the GRE exam and the topics it covers under Quantitative and verbal to have an understanding about how you need to start preparing for the exam.You can most probably write the exam in your 2nd year or final year depending on your convenience and when you are planning on applying for universities.Prepare on a regular basis using standardized materials most of which are available online or easily available in paper format.Create your own calendar for study and prepare well.All the best!!

1. Browse through the free official preparation material on ETS website. This wouldn't take much time. The powerprep software provided by ETS gives a good starting point. Just give one of them in a timed condition. You will know where you stand and what areas to work on.

2. Just start building up your vocabulary because that's the part in which preparation matters a lot. You can start with Find out how strong your vocabulary is and learn new words at Vocabulary.com... It has several special lists for common GRE words like the Kaplan 300 list, Princeton Review's Hit Parade and several lists from Barron also. Preparing through it is less like preparation and more like playing.  There are other things about which I think other people will surely advise in their answers.

P.S. - I will add more things if I get time sometime. What I have written is, according to me, at least a good way to get started

Hello Vishalini! Yes, definitely. You can start preparing for GRE from second year of graduation also. Prepare well and get through it. All the best for it!