Go to the Vacancy Record Shortlist tab or a Candidate Record Shortlist tab, and click the shortlisted record from the list for which you need to show as an already submitted one. The candidate information appears in a box to the right of the window.
Click Already Submitted and the following window appears where you need to select the date and time at which the CV was submitted, and add any notes if required.
You can also set a reminder if you need to do any follow up for this CV by selecting the Tick to add a reminder check box, and selecting the consultant and setting the date and time for the reminder. You can also see here for more information on setting reminders.