WooCommerce Ultimate Upsells Demo. To see the upsell function in action:
(1) Add the “Hoodie” to the shopping cart.
(2) Click “view cart”.
(3) Click “proceed to checkout” at which point you should see the upsell popup where you can add upsell products.
(4) Then proceed to checkout at which point you should see your initial items in addition to those that you added in your shopping cart.