Every dDrive has a title, description and a thumbnail. To change them, open the "Drive Properties" dialog and make your changes.
You can reach this dialog in multiple ways:
From The "Site Info" Button
Visit the dDrive, then click on the "Site Info" button (the blue button on the left side of the address bar). Then click "Tools" and select "dDrive Properties."
From "My dDrives"
Open a new tab and look in the "My dDrives" section. Right-click on the dDrive you would like to edit and select "dDrive Properties."