Customers Order History
From the main Customers window you can easily see the Order History for each of your customers.Click on the Show/hide customer info pane button as highlighted in red to view the pane if it isn't already showing.
The Customer Info Pane shows all the orders allocated to the customer in chronological order with the newest at the top.
You can double click on record to open the order to view or amend. It's worth noting that the view here doesn't refresh real-time, so if you make any changes to an order, you would need to click onto another customer and then back onto the original customer to refresh this view.
You can also right click on an order in this view to create a copy of the order which is automatically allocated to the customer.