There are several key steps in the development of clothing construction:
1) Humans began wearing animal skins and furs for protection, modesty, and appearance starting 100,000-500,000 years ago. Sewing was initially done by hand.
2) The invention of the sewing machine in the 1800s revolutionized garment production by enabling mass manufacturing. This led to the rise of ready-made clothing industries.
3) Proper fitting involves five factors - ease, line, grain, set, and balance. A well-fitted garment is comfortable and looks balanced from all angles.