Step 1: Login to Google Merchant Center
Step 2: Click on Product Reviews tab found on the left navigation bar
Note: If you don’t find product reviews, then you need to fill out the Product Rating Interest Form by Google. This will import the ratings from your product page to the Google Merchant Feed.
Step 3: Then click on ‘+’ icon found under Feeds
Step 4: To register a new feed, use the following input
Step 5: Choose the input method by choosing Scheduled Fetch and click Continue
Step 6: Set up the feed with the following information
If the file is protected with username and password, please define them, else you can leave the following two options empty.
Step 7: Click Save to complete the process.