Measure the opening of the cabinet and determine what length is required for the top and bottom tracks. Make the measurement flush to the side boards of the cabinet. Cut the top and bottom sliding door tracks with a saw to fit this measurement.
Position the top track, which usually has a deeper groove, against the top of the cabinet, flush with the outside of the front surface of the cabinet. It should still be in a position where the ends of the track butt against the side board of the cabinet. Drill 3/4-inch wood screws through each hole and into the top board of the cabinet to attach the top track.
Hold the bottom track perfectly parallel and even with the top track but against the bottom board. Make sure it is the same distance from the front of the cabinet as the top track by measuring with a tape measure. Attach the bottom track in place with 3/4-inch wood screws drilled through each of the attachment holes.
Measure the height of the cabinet opening and subtract 1/2 inch plus the height of the casters from this measurement to find the height of the plywood doors. Measure the width of the cabinet opening and divide it by two. Add 1 inch to this measurement to find the width of the plywood doors. Cut out two pieces of 1/4-inch-thick plywood to this height and width.
Position two 1/4-inch-thick, fixed casters evenly against the base of each plywood door. Attach them in place according to their design. Use 3/4-inch wood screws drilled through the attachment holes of the caster, or drill a hole for each caster and screw the caster itself into the hole.
Set the plywood doors in the sliding door tracks by angling in the top of the door first and then lowering the bottom section with the wheels into the tracks.
Position a doorknob in each desired location. Mark the position of each doorknob bolt hole. Drill out the hole with a drill bit slightly smaller in diameter than the doorknob bolt. Slide the doorknob and attached bolt through the hole and tighten the nut on the other side with a wrench.
Position a latch between each of the doors and its adjoining cabinet side board. Mark the holes for the latch on each section. Drill out each hole. Attach the latch bolts in place with the included nuts using a wrench.