creation of a basic concept and a draft model (low or mid poly model)
after approval, we detail the model, make a sculpturing. as a result we get a high-poly model.
model optimization: manufacturing of a low-poly model that repeats the basic forms of a high-poly model.
baking of maps (normal, ao, curvature etc.), i.e. baking of details of a high-poly model on a low polygonal model by means of texture maps.
giving the model color, material properties, aging elements, not perfect, etc.