Represent now another circle under the first circle’s layer. The color’s code is 818181.

Then open a new file having 4×4 px and 72 dpi. Use the next instrument on it to insert 4 pixels diagonally on a transparent background.

Select now Edit Define pattern… and save the picture! Get back to our actual file and apply the next adjustments for the circle.
Blending Options:

Choose the picture in the Pattern option.

And one more circle represented with the usual tool . Its color’s code is 112840.