Step Two: Dadoes

A dado is a groove made in a piece of wood by running a blade through it at a shallow depth. Dadoes are much easier to make on a table saw, so if you have access to one, by all means use it. Set the blade depth on the circular saw to 3/8" of an inch. Test cut on a piece of scrap to ensure the blade depth is accurate. Run two cuts on the underside of the top (the side that is more flawed), parallel to the long side, at 1" in from the edge and 1-3/4" in from the edge. Set the blade depth to 1/8" of an inch. Repeat the above cuts, mirroring them in the 3" strip of wood that will be the bottom track for the doors.

It is important that these cuts be super accurate, so take care in setting up the straight edge. The depths are also important, as they allow enough play in the doors to make them removable if need be. So again, take care in registering the saw and make some test cuts to confirm accuracy.