A drop shadow for lettering illustrates a 3-dimensional quality of an object. When a light source is introduced, the drop shadow falls on the opposite side.
The drop shadow is usually a much darker color than the letter, in order to create a contrast.
However, if the letters are dark, a lighter color can be used for contrast.
When using a pounce pattern, it is easy to just drop the template to create the border of the drop shadow. The thickness of your drop shadow is a judgement call on the artist and the desired effect. A few common reasons for a very thick drop shadow would be: To create the illusion of a very thick letter; or a light source that comes from a dramatic angle.
Use the right tools and brushes to paint the drop shadow. Use a striping edge and striping brush to quickly and accurately block in the straight shadows. Use a lettering brush for the curves and flat edges.