Promo Codes is used as follows: Make sure you have an account in Swell Reptiles; if not, you can create one first, then select your favorite products to add to your cart. Then, click the Calculate button, and finally jump to the payment page, you will see the information of [Select your Coupon Codes], click to select the Coupons you want to use, and then return to the payment page to continue to complete the payment. Please note that used Coupons will be automatically removed from your coupon.