Since millions of years ago, potters have been moulding and curating vessels using clay bodies, thus recording pottery as our oldest handicraft.
Pinch pots, made from balls of clay into which fingers or thumbs are inserted to make the opening, may have been the first pottery.
In prehistoric times, woven baskets were lined with river clay and filled with most likely water. These baskets were emptied of its contents, causing, the layer of clay dried. Due to the loss of moisture, the clay condensed and shrunk, causing it to unattached to the rim of the basket. The clay is now shaped like a pot.
It was then realised that moulded pottery could be solidified in hot ashes to make sturdy containers for the transportation and storage of food.
The first batch of pots were ignited at low temperatures, thus they were fragile and porous. This was somewhat resolved when ancient potters used rock or hard wood to polish the surfaces before firing. However, these resulted in the pots being blackened by these fires.
Decoration was generally the result of incisions or insertions of tools into soft clay. Early potters created objects that could be used for practical purposes, as well as objects that represented their fertility gods.
From these would have been extended the pots formed by hand and decorated with crude tools.
H/T Lakeside Pottery and Encyclopedia.com