Using the Selection Tool, set to ellipse, feather 0, antialias checked, start about where the red X is in the image below, and draw an ellipse. Don't worry if it's perfectly centred, because you can move it later.
Flood-fill the oval with #0F0A42 (if you use black, the bevel doesn't show very well.) Go to
Selections - Invert
Hit CTRL-X
Selections - Invert again
Effects - 3D Effects - Inner Bevel - Frame preset.
Congratulations! I hope you enjoyed this tutorial.