Here is the Delaware Library's OverDrive page. You'll need to login to your library account with your library card number in order to renew your ebook(s). Click on the little books icon to view your loans. When the Renew option is available for eMaterial you have checked out, you'll see a Renew button under the item. Simply click on it to renew the item. You can also manage your eMaterials through the Libby app, if you have it on your mobile device.
You may want to see OverDrive's area for steps for how to renew an ebook for further information.
If you have any trouble, please contact your Delaware library staff for help - we're happy to assist!