By default, your presentation is set to be “Public.” This means it's available to everyone under "Presentations" in the main menu of the On-Demand player. Here's how to hide a presentation by changing it to “Private."
From your Dashboard, click the On-Demand “Presentations” link.
Click the presentation you want to make private.
Under the presentation title, click the “Settings” tab.
Click the “Edit” button in the “Playback Options” section.
Toggle the "Visibility" button to “Private” and click "Save."
Now when you preview your On-Demand player, the presentation won't appear under "Presentations" in the main menu. You can still view and embed private presentations on a web page.