With a disappearing-ink pen, mark 2 lines parallel to the bottom edge, as indicated by notches on template (one 20 1/4 inches from bottom, the other 16 inches above the first). Fold the apron so the vertical lines meet, creating a pocket. Iron in place.
Use the disappearing-ink pen to mark lines where the pocket will be divided into compartments (we drew 2 lines to create 3 pockets).
Sew to the left and right of each line (about 1/8 inch apart) to create compartments. Sew a 1/4-inch double hem on all edges of apron except bottom.
Sew a 2-inch double hem along bottom. Add neck straps, as described for the gardener's apron. Using the same method, add 2 long waist straps (each will start as a 2 1/2-by-34-inch strip).