One Card will be easiest to get. Else open a bank account with IDFC, HDFC, Axis Bank and maintain some good balance like 30-50K and do some good transactions for 3-4 months. Then you will be given pre approved offers which is the easiest way to get.
Heard someone people who regularly do transactions on Flipkart got FK Axis and on Amazon got Amazon ICICI. Hope this helps. But having the bank account is the easiest way to get.