First: Browse the website and find the items you want. Add at least 2 items to your cart. 

Second: From our selected collection, add 1 more item to your cart. Then go check your cart, at this time, the price of the newly added item will be $0. And you can see the discounts will be applied.

Third: Make sure you add the right product. Then click Check Out. Double check if the code has been applied. If you see the same as the screenshot in your check out page. Feel free to finish the payment! :)