The four well-know techniques to make sculpture are:
Craving using stone, wood, ivory or bone.
Modelling in clay or wax.
Casting is a very popular method, where liquid in the form of bronze is poured into a cast and hardened.
The lost wax process is a technique used to produce casts where a clay and plaster mould take on wax which is melted through a vent and molten metal is poured in to replace it.
Sand casting is another simpler technique that uses moulds made out of compacted fine sand.
Assemblage sculpture is a technique that involves the collation of several different, often found materials and objects within one work.