The first goal is to create grooves in all the rails and stiles to accommodate the 1/4″ thick panel. Now, you can usually use a Dado blade for this.
Once the grooves are cut in all the boards, it is time to cut the tenons (or tongue) at the end of the rails.
Once the rails and stiles are cut, it is time to get an accurate measurement of the panel needed to complete the door.
We are now ready to put it all together.