Yes – follow these steps and it should be straightforward.

1. Find out what your blog’s existing header image is called and find out its dimensions. The easiest way to do this is to display your blog in your browser and right-click the header. Depending on your browser, you want to click ‘Properties’ or ‘View background image’ or something similar which will let you see more information about the image. Note the filename of the image and its dimensions.
2. Now you need an image that you want to use instead. Open the image file in PhotoShop or Elements or some other image processing software. Crop and/or resize it to make it the same dimensions as your blog’s header. Then save it somewhere on your computer with the same name, and in the original image format (.jpg, .png, .gif), as the original header.
3. Then you’re going to upload your image to overwrite the one on your blog. Go into your FTP program, log in and navigate to your blog’s WordPress files. To find the header file, drill down to:
   • wp-content
   • themes
   • [your blog's theme]
   • images
4. You should see the image file in the file list there. It would be a good idea to rename this file so that if there is a problem you can rename it back to what it was. Now simply upload your amended image in place of the original header.

Now display your blog (you may need to refresh your browser). If the images displays OK, congratulations!

If the above routine doesn’t work, check that you’ve done everything properly. If there is any problem it probably means that your theme’s author designed the theme in a non-standard format.  The best way to proceed is now to visit the author’s blog (link in the footer) and ask how to change the header. There’s a good chance that someone has already asked the question and your answer may be there.

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