One way to do this is:
Create a circle with the shape tool in Photoshop
Add Mask to the layer on which the circle is drawn
Create a New Layer and keep the layer selected
With the Pen Tool create a path around the area that needs to be masked.
Once the Path has been drawn go to Path - Load Selection. This will create a selection
Now select the layer on which the circle is drawn. Select the Layer Mask Thumbnail
Keep the Foreground Color as Black and use the Brush Tool for Masking
Now Deselect the selection
Now Press Ctrl + J. This will duplicate the layer. Ctrl + T and rotate the circle
Mask a portion of Yellow Layer for Overlapping
Create layers below the Shape Layers. Use Brush Tool to draw Shadows. Decrease the opacity to give it a shadow effect.
Draw a grey circle. Make e rectangular selection and copy to the clipboard one slice (=circle segment) of the circle.
Paste the slice to three different layers (Slice 1,2 and 3). Paste in place!
Take the selection tool. Rotate one of the slices +120 degrees and one -120 degrees. Enter the angles into the appropriate box at the top of the screen.
Move the slices at their places. They snap within 1 pixel if you have the snapping on.
Layer by layer: Goto Image > Adjustment > Hue/Saturation, cross Colorize and adjust the color. Now you should have:
Hide the grey circle. Goto the bottom slice layer. Select half of it and copy to the clipboard. Paste it to place and move to the top in the layer stack:
- make a new layer(=Shadow) under the source of the shadow
- draw a solid black line below the edge
- goto Filter > Blur > Gaussian Blur
- goto the layer that is under the shadow
- select the transparent area by the Magic Wand
- goto the Shadow layer and press DEL