A blacksmith's traditional toolkit includes a forge, for heating his or her workpieces, hammers, pincers and punches, and a special tool, called an anvil. The anvil is a large massive work area, with flat areas, curved areas, and pierced areas.
Much of a blacksmith's work involves shaping their workpiece, through hammering, on their anvil. Usually, part of the workpiece is heated by inserting it in the hot coals of their forge, prior to hammering. Hammering the hot region of the work over the flat part of the anvil might be used bend or flatten that part of the work. Hammering over a curved area can impart a curve to the work. Holding the work over one of the holes in the anvil, and hammering a punch over the anvil's hole, can pierce the work with a hole of its own.
A blacksmith's training allows them to use the color of the work to guage its temperature - important to know when to work their piece.
Blacksmith's know that if they heat their work above its curie point they will erase any magnetic fields in the work. Heating to higher temperatures allows them to manipulate qualities of the piece, including its brittleness, ductility, hardness.
Smith's also have ways to use the heat of their forge, and quenching baths, to manipulate the size of the crystal in their work.