Using the Ellipse Tool (U), try to represent the central element of the logotype. Place its layer lower than the top layer of the logotype.
使用椭圆工具(U)在图标的中心画一个圆形,将它放在顶层之下

The layer parameters: Fill 0%
Blending Options>Drop Shadow
图层参数设置为:填充:0%
图层样式(参数如图):
投影

Blending Options>Inner Shadow
内阴影

Blending Options>Gradient Overlay
渐变叠加