1) Click on 'Orders' in the side left menu bar then click on the backer name.
2) Click the 3 dots and a drop down will appear. Click 'Mark as Shipped'
4) This will bring up a popup window verifying that you would like to mark this customer as shipped. Click the green Shipped button.
5) Now you can filter your orders to only show you the orders that have been marked as 'Shipped'