Step 1: Prepare the wall

Choose a location for the ironing-board cabinet. Place it near an electrical outlet. Keep in mind that the board will extend 42" when open.

Use the stud finder to locate and mark two adjacent wall studs.

Mark the wall between the studs at the height at which the bottom of the board cabinet will be, and draw a level line along the mark.

Place the cabinet against the wall with the bottom lined up with the level line. Use the back of the cabinet as a template for drawing a cutting guide.

Step 2: Cut an opening for the cabinet

Use a dry-wall saw to cut an opening for the cabinet along the lines on the wall. There is no need to rush. The cut doesn't have to be perfect, but try to make it as neat as possible. If the marks don't line up perfectly with the wall studs, don't worry. Just compensate to make the cut along the studs. Hold the dry-wall saw at an angle, with the tip pointed upward. This will reduce the risk of damaging the far wall.

Step 3: Cut the cleats

Cut two 10" pieces of 2" by 4" finished lumber to use as cleats to support the weight of the cabinet. Drill pilot holes so that you can toenail the cleats in place. Use a drill bit that's as close in size as possible to the diameter of your wood screws.

Place the cleats flush with the top and bottom of the cutout, and mark them to make sure they don't slip while you're securing them to the wall studs. Screw the cleats into place.
For easier mounting, start the screws into the cleats before placing them in the wall opening.

Step 4: Attach the cabinet

Place the cabinet in the cutout. Use shims to adjust the cabinet so that it's level and plumb, and secure it with screws. Assemble the ironing board, and attach it to the cabinet. Attach the door to the cabinet.