In some cases, the actual skin (including the fur, feathers or scales) of the specimen is preserved and mounted over an artificial armature.

Tanning the skin

In other cases, the specimen is reproduced completely with man-made materials.
the word 'taxidermy' is derived from two ancient greek words; taxis, meaning movement; and derma, meaning skin. therefore, loosely translated, taxidermy means the movement of skin.
This is a fairly appropriate definition as many taxidermy procedures involve removing the natural skin from the specimen, replacing this skin over an artificial body, and adjusting the skin until it looks life-like.

sculpting the form

 The modern practice of taxidermy incorporates many crafts, such as carpentry, woodworking, tanning, moulding and casting; but it also requires artistic talent, including the art of sculpture, painting and drawing.