The invoice that you generate for your client should match what you are shipping. For this reason the recommended workflow for creating invoices is from Dispatch Dockets. For smaller companies where a single person is both dispatching and invoicing these processes can be combined, view this article for more details on this workflow.
Whist orders are open in the system (not dispatched) they are shown in the WIP (work in progress) screens. Dispatching jobs allows you to quickly determine any jobs that have been dispatched but not invoiced.
To manage the Dispatch Dockets that require invoicing, from main WIP screen click Dispatch List . This will load a historical list of all dispatch dockets which also includes the Invoice status for each one.
Each Docket will display as either Invoiced  with a link to the relevant invoice or Not Invoiced  with a Red Flag showing. To invoice simply click the [+ Invoice] Button.