A simple text widget with Title, Image URL, A text/html area, Link Text and Link URL. This simple widget is often used for a call to action widget.
Use the media manager to add a new item. If you click edit on the image you can find its URL and copy and paste that into the widget. You can also upload images via FTP or link to images on other websites.
Edit your theme's style.css file or any other CSS that is loaded on the website. There are class names for each element of the widget and there are example CSS configurations on the plugin site.