I made two changes to better fit a child's head:
(1) I made the head scarf reversible and
(2) I cut the fabric rectangle a bit smaller
The pattern calls for one 17 1/2" x 8" inch rectangle of fabric for the scarf.
To fit a child's head, I cut two 16" x 8" rectangles in complimentary fabrics.
Next, the pattern requires that you turn and press the two long edges of the fabric and top-stitch along these edges.
To make the scarf reversible, I sewed two 16" x 8" rectangles of complimentary fabric along the long edges, right sides together. Then I turned them right side out, and followed the remainder of the sewing instructions in the book.
Truth be told, I made a green head scarf first. In this one I top-stitched along both long edges after I turned the rectangle right-side-out. I did this so it would look more like the version in the book, but I wasn't happy with the stitching so close to the face.
So there you have it. Two modifications. Two cute and simple scarves. Let me know if this helps.
Enjoy your weekend!