You can see another of Gormley's sculptures on the Tate website.
A sculptor might use tools or just their fingers to create the shape they want. Why don't you have a go? Try moulding some salt dough with a range of tools - spoons, fingers, pastry cutters.
You can get a recipe for salt dough here. Might be a good idea to ask an adult before you start cooking though.
The salt dough recipe is from the National Portrait Gallery website.
Gormley picture © Arts Council Collection, Hayward Gallery, London; purchased with support of The Henry Moore Foundation and the National Art Collection’s Fund.