During your order procedure and prior to your payment through PayPal you will be able to remove part or all of the products from your shopping cart by pressing the Delete button which is next to each of your products in your shopping cart. You will also be able to add more products or change the quantity of the products in your cart.
If you choose to pay though PayPal and wish to cancel your order once you reached the payment page you can press the “Cancel and return to ARVO website” button.