1. Before you start making this tutorial, go in the View menu and check if the Show Rulers and Snap options are on. Now drag the vertical ruler (left) to the center of your image. Do the same thing but with the horizontal ruler (top). Now there should be a cross right in the middle of your image.
2. On a new layer, use the elliptical marquee tool to make a circle, make sure that the circle's center snaps to the center of the cross. After making the circle, fill it in using the paint bucket tool with the color of your choice.
Make a smaller circle inside of the circle that you made, and hit Del. This should leave you with a ring. Like the one on the left.
3. Now make a thin rectangular line using the rectagular marquee tool. Make sure its width is bigger than the circle's and center it on the cross. Press Del to make the circle into two segments.
4. Now with the rectangular line selected, right click on the selection of the line and rotate it 90° CW or 90° CCW. Hit Del once the selected area is in a vertical position.
5. Finally, right click on the selection and rotate it diagonally (It should be in the middle of two segments). Hit Del; do the same with the other side of the circle, you should now have 8 segments. Make further changes if you wish to. :)
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