To apply a coupon code, it can be entered in after taken to the checkout page (after clicking on the "Enroll in Course for $XX" button).
1. Under "Review Your Order" there is a blue "Redeem Coupon" button in the grey Total row.
2. After clicking this, a text box should appear where you can enter in a coupon code.
3. After clicking redeem code, the page should refresh and the price should be adjusted. Continue on with entering your Payment information.