Try this: Create the texture you want, in this case red and white stripes and dirty blotches, in whatever graphics software you have. Now, Illustrator and Corel do this automatically, but you might have to do it manually. Basically you want to split the image into four corners, and swap them diagonally. Now the image will wrap neatly, the left side lining up perfectly with the right side, but of course you will have an uneven cross shape through the middle of the image. Use smudge, blend or clone tools to fix this up and voila, you have an image that can tile indefinitely with no discernable line between tiles. I can do a bit of a tutorial on this if anyone is interested and this isn't clear enough.
