Select a decorative pedestal to use for your table's shaft. It should be 25 to 28 inches tall and made of wood or solid plastic.
Cut an 18-inch circle out of a piece of 1-inch plywood with a jigsaw.
Use a router with a rounding bit to give the cut edge of the circle a rounded finish.
Flip the circle over and router the other side.
Set the pedestal on the ground upside-down. Place the wooden circle on it, centered in the middle of the pedestal.
Drill four pilot holes in a square through the circle and into the pedestal.
Screw four 3-inch wood screws into the pilot holes to secure the circle in place.
Flip the table over. The circle will be its base.
Cut a 3-foot circle out of the plywood and round the edge with the router. This will be the table top.
Center the table top onto the pedestal.
Drill four pilot holes in a square and screw the tabletop to the pedestal with 3-inch wood screws. Countersink the screws slightly below the surface of the table.
Fill the screw holes with wood putty. Smooth it as level with the table surface as possible and allow it to dry.
Sand the wood putty with 100-grit sandpaper, then again with 200-grit and a third time with 300-grit. This will smooth the wood putty's surface, making it indistinguishable from the tabletop.
Apply three thin coats of spray primer to the entire table, allowing each coat to fully dry.
Paint the table in the color of your choice.