Background Image Issues

I have been trying to change the background for my homepage. I started by uploading the image from the page I wanted altered, and then I made sure it was selected ‘background image’ instead of using the default. It didn’t work. I tried changing the color instead, and that worked, but I want to use a background image. I also tried making the default as an image to see what would happen, but that doesn’t seem to work either.

http://www.cayceberryman.com