Design your ping-pong table around a pair of wooden sawhorses as the primary support components. Use the International Table Tennis Federation's established standards for guidelines. Your sawhorses will need to be modified to give you the required table height of 30 inches.
Cut two sheets of your selected sheet stock material into 4 foot-by-5 foot sections. Cut two pieces from the third sheet 6 inches wide by 5 feet long for splicing to the larger segments, to make up the needed 4 1/2-foot length for each table half.
Cut three pieces of furring strip, each 5 feet long. Predrill two of the furring strips for deck screw attachment as cleats (drill along two sides), and one of them as a half-cleat (drill along one side only). Sand rough edges and surfaces.
Attach the large and small tabletop segments to make two 5 foot- by-4 1/2 foot table halves using the furring strip cleats and deck screws, along one of the 5-foot edges. Attach the third furring strip cleat to one of the segments, at the center, where the two table segments will be connected when set up for game play.
Modify your sawhorses so they stand at the appropriate height to support your tabletop at a level and flat 30 inches high. Take the tabletop thickness into account when calculating the correct length to cut the sawhorse legs. Sand rough edges and surfaces.
Attach your 5 foot-by-4 1/2 foot table top segments to your sawhorses using adequately sized, counter-sunk deck screws. Don't be stingy with the screws; make the attachment strong. Use wood filler over the screw heads. Placement of the sawhorses should allow each table segment to stand alone -- balanced -- without falling over.
Paint the ping-pong table playing surface with green or blue flat or matte latex paint.
Finish with a white stripe around the perimeter and along the 9-foot center line using white vinyl tape or white paint. ITTF regulations call for a 2cm-wide (about 0.8 inches) white stripe.
Set up the table by placing place the two table halves together so the third furring strip you attached on one of the segments supports the other segment. Clamp together with small C-clamps. Clamp on your ping-pong net and volley.