Properties of the images, audio, video, flash, links and YouTube video that are already inserted in the WYSIWYG editor can be edited. The same dialog that was displayed when you inserted the items can be opened again the following three ways:
1. Double-click the item
2. Right-click the item and choose Properties from the context menu
3. Select the item and click the appropriate button in the WYSIWYG editor toolbar
Page url: http://devnet.kentico.com/docs/devguide/index.html?editing_inserted_items.htm