Open the Amazon app or website
Sign in to your Amazon account
Go to the product you want to buy
Check whether the item accepts Amazon Diamonds as a payment or reward option
Add the item to your cart
Proceed to checkout
Select Diamonds as the payment method if available
Apply the Diamonds balance to the order
Confirm the remaining payment method if Diamonds do not cover the full amount
Complete the purchase
Review your order confirmation to verify Diamonds were used