Creating an amused smiley

Start by creating a circle using elliptical shape tool.

Double click the layer to open layer style window. Apply layer style with the settings shown.

Create an ellipse using elliptical shape tool. Create a new layer. Apply Black to white gradient. Change layer mode to screen for this layer.
Create an ellipse using elliptical shape tool. Press Ctrl+T. Right Click and select Warp. Adjust the nodes to get the shape as shown.
Double click the layer to open layer style window. Apply layer style with the settings shown.

Create a circle using elliptical shape tool. Apply glassy look using same steps we used for face layer.

Create a small black circle for the eye ball using elliptical shape tool.
Duplicate all the eye layers. Press Ctrl+T. Right click and select Flip Horizontal and place on the other side.
Create mouth shape using pen tool. Apply same layer style we used for the eye.
Create an elliptical selection using elliptical marquee tool. Press Shift+Ctrl+D to feather the selection. Create a new layer and fill it with black color. Move this layer below all the layers in layer order in layer palette.