On the dashboard, you can use the “Order without shipment” widget.
Add "Order without shipment" widget
1. On Dashboard tab, on the left hand side of the screen click on "Add Widget"
2. Click on "Add" for the wanted widget
The widget is listing all the PO (purchase order) that have been created for which no shipment has been created yet.
From the widget you can create a shipment (see How to create a shipment?)