Photo 4-Hand chop mortises in the legs with a sharp chisel. Make the mortises small at first, then test the fit of the shelf stock in them, and then widen them until you have a snug fit.

Mark out 1/4" deep mortises on the legs as shown in the drawings, then chop them with a chisel as in photo 4. Next set up at the table saw with a mitre gauge to cut bevels on the tops of the legs as in photo 5. Note that you could use a similar setup with a dado set to cut the mortises, but you would not want to cut through all the way across the width of the leg with the dado. So, you would need to stop the dado cut before it goes all the way through. In this case the dado would cut most of the mortise but not all, leaving a curved bottom, and you would need to clean up the rest of it with a chisel. For this reason I cut the whole thing with a chisel. But, using a dado has the added advantage of creating clean and straight mortise walls, so if you are unsure of your skill with a chisel you may opt for this additional step for the sake of machine accuracy.

Photo 5-Cut 45o bevels on the tops of the legs with this simple setup on the table saw with the mitre gauge.

Complete the legs by smoothing their faces by sanding or with a handplane as in photo 6.