To get started, scroll over the header image and click the Edit Image button.
Now you can Select a Background from a set of high quality stock images geared toward a variety of applications (and you can sort by Category in the top right). Or you can Upload an Image of your own via the button in the bottom left. Choosing this option opens up our standard image upload box.
Once you upload or find an image, you'll be able to alter it.
You can move the image up and down within the header (it will already fit to the width of the page), zoom, blur, darken or add a filter.
When you're happy with an image, select the Save button to Save it. You can use the arrow to the right of the Save button to choose whether to save the image to every page of the site, just this page or to select only certain pages to save it to. In that way you can have different headers on different pages if you want.