Basic instructions: sew up a tube using stretch fabric, the circumference of which equals the baby's head circumference less 1 cm. Draw 4 darts at the top (about 2-3" long--these were a little too short so the hat was too boxy):
Stitch up 2 darts on opposite sides:
Stitch up 2 darts on opposite sides:
Stitch the remaining 2 darts in one long seam:
Turn up a deep hem and stitch:
Done!