Measure the cabinet opening
Decide the door overlay or inset style
Choose your wood species
Cut the stiles and rails to size
Cut the center panel to size
Mill the stiles and rails with groove or mortise-and-tenon joinery
Cut the panel groove in the stiles and rails
Shape the rail ends and stile joints
Dry fit all parts
Sand all components
Assemble the frame without glue first
Apply glue to the frame joints
Insert the center panel
Clamp the door square
Check for diagonal equality
Let the glue cure
Trim the door if needed
Sand the assembled door
Fill any gaps or imperfections
Apply primer or finish
Install hinges and hardware
Hang the door on the cabinet
Adjust alignment and reveal gaps
Add handles or knobs