Hello Janaki,
As Rashid had guided you properly on how to prepare, and others had given you all the tips for documents, let me add some suggestions only.
1. Always carry a writing pad so that if the interviewer asks you to make some notes or work out something, you should be ready to take action.
2. Carry your passport-size photo, at least 2. Sometimes it is required in some companies.
3. DON'T FORGET TO CARRY YOUR CONFIDENCE... THIS IS THE MOST IMPORTANT THING.
4. If you have work experience, then carry the supporting documents (like experience certificate, appreciation letter, salary slip copy).
5. If you are a fresher, then carry your project copy (if it aligns with the job profile). It will help you present your candidature to the interviewer and give an idea about your working pattern.
6. Be ready with your SWOT Analysis. It is useful for presenting your complete profile when the question is asked, "Tell me about yourself?" Don't use the word weakness; instead, use it as areas of improvement. This shows how much you are aware of yourself and your learning attitude.
See the PPT attached herewith; this will give you more ideas.
BEST OF LUCK!