Showing free shipping signs on product or checkout pages is a great incentive for customers to purchase a product. To make sure the product has free shipping, go to: Control Panel > Products > Select a product > Go to Tax and Shipping tab > Specify "Shipping freight" as "Free".
Now, to show customers that these products have free delivery, use the following options:
Update the product image to add a free shipping note or a badge
To do that, first find a small icon or image that you wish to use. Then get your product image that you uploaded earlier and edit it in any image editor to add that icon to the product image. After that, update product image for that product.