From the website of Reddit, you can check the list of Old Navy promo codes that you can use for your online order. Many people like to share coupon code for Old Navy on it so you can use them as another source to earn more savings when shopping online.
If you want to redeem Old Navy super cash in store you need to show the SUPER CASH coupon to the cashier at checkout. After the cash is checked, you can enjoy money off on your online order.