I am no expert in immigration issues, but here's what I think.
1. You should get letters from all the employers you've had in past years.
2. I don't know which documents would be best for this part.
3. IELTS is not too difficult. If you speak English, you shouldn't have a problem. However, you should check for a test date, as sometimes one has to wait for a few weeks before a date is available.
4. You need to provide Police Certificates from every city where you have lived since the age of 18 So, you would need cirtificates from both, Mumbai and Bangalore.
5. Bank statements and letters from the banks certifying the amount of money that you have, Keep in mind that is's $10,601 CAD.
You'll be able to find more detail in this website.
http://www.cic.gc.ca/EnGLIsh/pdf/kits/guides/E37029.pdf