Instructions for this image:

1.  Erase to Black.  (Ctrl - K)

2.  Color Noise setting 500.  (Ctrl - Alt - P)  Repeat three times.

3.  Select the Selection Tool from the toolbox.   Start anywhere near the center of the image, and select an area that's Width 6   Height 6.  Crop to selection.  (Very tiny image)

4.  4way Flip.  (Alt > I > S > F)

5.  Smooth Resize to 256 x 256.  (Ctrl - R)

Note - this final image was lightened so the text would show up better.