In your store's Admin area, go Go to the Extension > Shippings > Free → Shippings → Free shipping
Sometimes you want to give your customers an option not to pay for shipping their orders.
Total: - Sub-Total amount needed before the free shipping module becomes available.
Location: - select the proper location
Status: - MUST be "ON" for Shipping module to appear in your store.
Sort Order: - Sort Order set's the order of in which the Shipping will be displayed amongst others.
After you have made your changes, select the SAVE button.
Note: there is are several other methods to allow products with free shipping. You can create Coupon with Free Shipping option and each product have Free Shipping setting. This methods method works separately from Free Shipping Extension!