Drawing a cartoon snake

Start by applying gradient to the background layer.

Create a circle using elliptical shape tool. Apply stoke layer style.

Create an ellipse for the eye using elliptical shape tool. Create a circle for the eyeball using elliptical shape tool. Press Ctrl+Alt+G to create a clipping mask.

Create a very tiny circle inside the eyeball. Duplicate these three layers. Select and rotate these three layers to create the other eye. You can resize the eyeball to break the monotony of uniformity.

Using pen tool create teeth and tongue. Color them as shown below.

Create a rectangle using rectangular shape tool. Press Ctrl+T. Right Click and select Warp. Adjust the nodes to get the shape as shown.

Enable add to shape area from the top bar. Again create a rectangle and warp it to get shape shown below.

Repeat the above steps to create a complete snake body.

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

Create a dark green circle. Apply stroke layer style. Press Ctrl+Alt+G to create a clipping mask. Press Alt key and drag this circle layer to create it's more duplicate that are automatically clip masked.

Using pen tool and brush tool create eye brows and nostrils etc. Also create two circles for the nose.

Select and merge all layers. Duplicate layer. Enable lock transparent pixels from layer palette. Fill it with black color. Press Ctrl+T. Right click the layer and select distort. Adjust nodes to create a perspective shadow. Reduce opacity.