Use a good art program, you may have one or download the free "paint.net" at:
http://www.getpaint.net/download.html1. Open a new 256 x 256 pixel 8-bit bitmap(.bmp) sheet.
2. Color it black.
3. Draw a white [X] one pixel wide from corner to corner. This will give you your center dot and a construction grid.
4. Draw anything that works for you in any color that works for your eyes including the center dot which is still white at this point.
5. Remember to zoom to about 1200% and make sure no pixels are closer than about 4-pixels to the edge of the black background.
5. When done clean up the remenants of the original white [X]. At 600-800% zoom you can do this one pixel at a time for neatness.
6. Copy it to the sites directory for the game and test it offline.
7. In the cockpit if the edges smear or streak outwards on the reflector plate, edit the file, zoom to 1200-1600% and make sure all color pixels are 4-pixels away from the black background edge.
8. Using a "Blurr" effect or sharpening the "luminosity" or both can remove the jagged edges and monochorme look to the color. But its not required.