Using the same instrument, try to make a small circle on the lowest part of the site’s panel:

The layer’s parameters:
Blending Options>Drop Shadow

Blending Options>Inner Glow

Blending Options>Stroke

Selecting the previous instrument, it’s possible to draw several more circles on the lowest part of the site’s panel:

The layer’s parameters:
Blending Options>Gradient Overlay

Gradient’s parameters: