In your dashboard, go to LANDING PAGES > MANAGE PAGES. At the top, click on +Add New Page (). Once there, you'll notice we offer a few different page types. Choose the one called Shopping Cart Landing Page and click +Add Page (). Once the pages is added, you'll noticed the mobile web page editor has an additional control for the Shopping Cart add-on. Click on the Shopping Cart Items button () to edit or add your items. After you're done editing your settings, you'll notice the changes will show up right away in your editor.