While transacting online, make sure that you are on a secure website before entering away your card details. How to make sure what is a secure website ? In your browser address bar, you should look for “https” followed by the name of the site. S – Means security in this case, which includes high level of encryption to keep your data safe while being transferred on the Internet. If you are not seeing a “https”, then please do not enter the details of your Credit Card and immediately call the merchant asking for other modes of payment.
Also, we should Thank RBI for having introduced an additional level of security to transact online – Verified by Visa or Master SecureCode – an additional password without which the transaction will not complete.
Once the transaction is complete, you should receive an e-mail from the online merchant, else, take a screen shot of the transaction confirmation [Saving the Web Page will not help, don’t do it]
Also a online merchant should have a return policy, in case if there is a mismatch in the product promised versus delivered then they should accept it back.