Kiddos's template apron measured approx 16"x23."
Step 1: Cut out the fabric leaving 2 extra inches on each of the sides and the top. If you are using regular fabric, the square would be 20"x27". I admit, I free-handed it. I figure no one is going to check to make sure that the bottom hem is perfectly straight.
Step 2: I used the backs of the shirts, so the shirt hem serves as the bottom hem of the apron. I turned under the sides and top and hemmed them with the raw edges tucked under.
Step 3: Then I folded the apron in half longways and cut the slanted sides at a 60 degree angle from the top. I wish that the top was not quite so narrow on mine, but they work. A quilters ruler and a rotary cutter came in really handy. here.
Step 4: This is where it gets cool. I turned the raw edge under and stitched it. Then I turned and sewed it again with a 1.25" gap so that the angle edge acts like a sleeve.
Step 5: I cut leftover material from the shirts into 2.5" strips and mitered them together to become very long (7 feet-ish). I pinned them so that they were folded around the raw edges and stitched them, so that they became long, somewhat stiff ties.
Step 6: I tied the thread tails to a pencil. I pushed the pencil through each sleeve and drew the tie through. The long tie goes up one side sleeve, around the neck, and back down the other sleeve. That way it is fully adjustable. I hate aprons where the neck loop is too big.
Step 7: The little boy apron seemed kind of plain so I picked the pocket off one of the shirts and sewed it onto the apron. Much better.
I kept making kiddo try one on to make sure it was the right size. She was a little bit a annoyed because it was not for her. Little does she know that I made the one from the embroidered shirt for her. She will find out Christmas morning.
Tomorrow, I will make the chef hats.