Download the templates. The adult hat measures 22 inches around (fits a medium size); the child's hat measures 21 inches (fits ages 6 to 10).
Tools and Materials
- 2 pieces medium-weight fabric in coordinating colors and patterns, 3/4 yard each
- Iron
- Disappearing-ink fabric marker
- Fabric scissors
- Fusible interfacing (optional)
- Sewing machine and sewing supplies
Reversible Hat How-To
1. Wash, dry, and iron fabrics.
2. Print and cut out templates for hat brim, side panel, and crown. Lay templates on first piece of fabric, trace with marker, and cut out. For a stiffer brim, lay brim template on fusible interfacing, cut out, and attach interfacing to wrong side of brim fabric.
3. With right sides facing, machine-stitch center-back seam of side panel with 1/2-inch allowance. Press seam with iron. Repeat with brim.
4. With right sides facing, pin crown to side panel. stitch with 1/2-inch seam. Trim seam allowance to 1/4 inch, and notch to ease curve.
5. Repeat steps 2 through 4 using second piece of fabric.
6. Returning to first fabric, pin brim to side panel, right sides facing, aligning center-back seams, and stitch with 1/2-inch allowance. Notch seam to ease curve.
7. Repeat step 6 with second fabric, but leave a 4-inch opening.

I have been a seamstress for 50 years and have never come across a pattern so ill designed. Come on Martha, you can do better than this.
Step 8 is missing- found in the magazine article to finish the hat.
There doesn't seem to be any instructions about getting the two hats together as one!