Consider what impression you want to achieve with your header–professional, creative, inviting or informative. If a picture paints a thousand words, what thousand words do you want viewers to read in your header background? A creative project, for instance, could use bright colors and non-standard design to convey a dynamic, imaginative project, while a more traditional professional project might use straight lines, solid colors and faint image in the background.
Think about eye-tracking, the direction a viewer's eyes are likely to move in while taking in the image in your header background. Remember that a viewer's eyes will naturally move toward more detailed or colorful parts of the image, so be sure the image leads a viewer's eyes toward the information you most want him or her to read.
Select an image that represents your project. Creative projects often use abstract images as a header background, while, on the other end of the spectrum, professional corporate materials usually opt for solid colors or photos with shading or transparency effects. Keep in mind that header backgrounds should be attention grabbing without completely focusing viewers on the header. You still want users to take in the rest of the information on the site or sheet.
Decide on a size and shape for your heading. Corporate materials often select a small heading in a traditional rectangular shape across the top of the page, just as projects wishing to convey novelty and imagination sometimes choose larger sizes that bleed into the content below with irregular shapes.
Open the image file you wish to use as a heading background in a photo or image editing program, such as Photoshop, GIMP or even standard software programs like Microsoft Paint.
Crop the image to fit the shape you have selected for your heading, either with a simple straight cut to make a rectangle or a manual shape with a cutting tool.
Apply colors and image effects to the picture, such as transparency, background color or shading. Remember that overly-detailed images can be very distracting for viewers and you will probably want to fade the image slightly to make it easier to view.
Add copy over the image. Use simple, bold fonts to add basic information about your project such as a name, short slogan or important directory information such as a contact address. Use a color that contrasts well with the image colors in order to highlight the text.