Draw out a plan for your chair or table on a piece of paper. Let your creativity take over, but design the chair or table with a rectangular or square frame. You cannot make a curved frame with PVC pipe.
Cut enough PVC pipe with a hacksaw for the legs, back and cross-bracing of the chair or table. If you are going to use cross-bracing for the legs, cut them in half. Deburr all the ends of the pipes you cut with 120-grit sandpaper.
Assemble the chair or table with PVC pipe fittings before gluing any of the fittings. Use 90-degree elbows or 3-way connectors to join pipes at corners, and tees or 4-way connectors to attach the cross-braces to the legs. Cut two runners that will stretch between each pair of legs and connect them to the leg bottoms with 90-degree elbows to prevent the ends of the pipes from scratching the floor.
Glue each joint in turn after the chair or table has been fully assembled. Using the brush that comes with the glue, spread glue liberally on the end of a pipe and on the inside of the fitting to which it joins and push them together quickly. The glue sets in less than a minute.
Cut a piece of 1/2-inch plywood for a table top or chair seat with a circular saw and sand the edges with 120-grit sandpaper to make them smooth.
Place the plywood on the PVC frame. Drill holes at 3- or 4-inch intervals along the edges, where they will connect with a pipe, using a drill bit that has the same diameter as a 1 1/2-inch carriage bolt. Drill the holes all the way through the plywood and the pipe until the tip of the bit emerges from the other side of the pipe.
Place a washer on a 1 1/2-inch carriage bolt and insert it into one of the holes. Place a washer on the other end and screw on a wing nut, but don't tighten it completely. Place bolts in the other holes in the same way and screw on wing nuts, then tighten all the nuts after the last one is in place.