Select wood or plastic that can be cut into a round shape and is sturdy enough to not warp under the pressure of the items being used. Hardwood plywood is most likely used in a kitchen-size lazy Susan. The larger the diameter of the top round and the heavier the items it is to be used for, the sturdier the material will need to be.
Choose the size of the lazy Susan bearing kit needed to support the size of your lazy Susan. Ball bearing hardware 12 inches in diameter can support a thousand pounds of weight. The lazy Susan hardware comes in many different sizes and strengths. It will determine how heavy duty your lazy Susan will be.
Design a stand for the lazy Susan to sit on. It can be built into a dining room table, or attached with a rod through the center and set into a corner cabinet. A freestanding Lazy Susan will have the bearings sandwiched between the top round piece that your items will sit on and a bottom piece like the cabinetry or a pedestal.
Design a rod to go through the center of the top, bottom and bearing casement. The rod will keep the three components together. You will not want the top or bottom sliding off the bearings.
Design two lazy Susans in a cabinet and insert extra support with dowel rods under the top round and the bottom round. This heavy-duty cabinet will turn together.