Lay a large sheet of canvas over your work surface. The fabric will prevent your clay from sticking.
Knead a large ball of clay to remove any air bubbles. Add a small amount of water, if necessary to make the clay more pliable.
Roll your clay out to a thickness of 1/4 inch, using a straight clay roller.
Cut five equal squares of the size of your choice from your clay sheet, using a clay cutter and ruler. Remove the excess clay from around the squares.
Allow the clay to dry and set for one hour, until the squares become stiff and leathery in texture.
Score the perimeter of each clay square with a pattern of X's using a sharp nail or clay knife.
Brush a thick layer of clay slip along the scored edges of each square, using a small paintbrush.
Assemble the pieces. One square will form the base of the pot, while the other four squares will form the sides. Gently press the sides against each other until clay slip oozes out from each seam.
Smooth out the edges and remove seam lines by rubbing a damp paintbrush along each edge.
Fire your clay pot in a kiln set to low heat, until thoroughly dry.