You can enter the discount code after selecting "Check Out" from your cart. You should see a box that says "Gift Card or Discount Code" on the right side of the screen when viewing on a laptop or desktop computer.
You may need to choose "Show Order Summary" if you are buying on mobile.
If you missed entering a discount code for an order you already placed, please reach out to help@brilliantperspectives.com and we will be happy to assist you.