Step 1
Measure the width of your dishwasher, typically either 18 or 24 inches. Add 1/2-inch to this measurement and note it down on a piece of paper. Measure and cut two pieces of 3/4-inch-thick plywood to 36 inches long by 25 inches wide with a reciprocating saw. Measure and cut another piece of plywood to 25 inches in length and width equal to the measurement you noted.
Step 2
Cut two pieces of 3/4-inch plywood to a height of 6 inches and a width of the measurement you noted in Step 1, less 1-1/2 inches. These pieces will form the backing support for the cabinet. If you are building a free-standing cabinet, you can replace these backing supports with one piece of 3/4-inch plywood of equal width to the backing supports and a length of 34-1/2 inches.
Step 3
Measure and cut a final piece of 3/4-inch plywood to 36 inches high by the measurement noted in Step 1. This will form the door of the cabinet. Glue one end of a support backing piece and attach it to the back of one of the 36-by-25 inch pieces at the bottom. Glue the other backing support and attach it at the top of the same 36-by-25 inch piece.
Step 4
Secure the other ends of the support backing pieces with glue. Attach the other 36-by-25 inch side piece to the backing pieces to form the frame of the cabinet. The backing pieces should be flush with the side pieces along the back of the cabinet. Stand the cabinet up and screw the backing pieces in place to reinforce the wood glue with 1-inch screws.
Step 5
Glue the top of the side pieces and the top backing piece. Place the 25-inch-long wooden top piece on the top of the cabinet. Allow the wood glue to dry. You can nail the top piece on if you intend to paint the cabinet; otherwise, the nails will ruin the look of the wood. Lay the cabinet on its back.
Step 6
Place the closed hinges on the edge of the left side piece. Mark the position of the hinges with a pencil. Scoop out the wood between these markings with a hammer and chisel so the hinges are flush with the wood. Screw the hinges in place in the holes. Stand the cabinet up. Screw the door onto the hinges. Close the cabinet door then screw on the handle.