Open up a new image, size 700×550 in PhotoFiltre. Save this image.
Pick a color you want to use as the background color. I’ll be using this color.
Now with the selection still there, move it over past the current colored bar and fill it in with a lighter shade of the previous color. We’re moving the selection over because we want the second bar to be the same length as the first.
Do steps 2 and 3 from this tutorial, click me!.