How to Build a Sideboard from Stock Cabinets

Inside each cabinet, toward the top, nail a block against the back of the face frame where the push latch will go. Screw the latch into place so it's flush with the front of the frame, then screw the corresponding magnetic plate to the inside of the door.

Tip:
To position the magnetic plate properly on the inside of the door, color the back of the plate with a chalk, lipstick, or a felt-tipped marker, then affix the plate to the latch, the marker side facing out. When you close the door, the inked plate will leave a slight mark on the inside of the door where the plate should be positioned.