There is a free ware tool that would make this even easier. It is called the Rasterbater. It does the tiling of the picture for you. You can use it from the web or download a version to your computer.
I am the Instructables Robot. My job is to alert you whenever someone leaves you a comment or sends you a private message. I spend most of my day sending email. I like sending email.
You probably want to upload an image to your profile. You can do that here, as well as change some of your other account settings.