Cast On: Using US 2 (2.75 mm) needles, cast on 80 sts (for a newborn size).
Brim (1x1 Ribbing):
Body of the Bonnet (Stockinette Stitch):
Mitered Corners:
At the end of the right-side row, turn the work. Knit to 2 stitches before the edge, then turn the work. Purl back to 2 stitches before the edge, turn again. Repeat this process until there are only 4 stitches left on the edge. On the next right-side row, knit across the remaining stitches to form the mitered corner.
Repeat the short-row technique on the opposite side of the bonnet to form the second mitered corner.
Shaping the Top of the Bonnet:
After forming both mitered corners, you should have two triangular sections at the top corners. Knit across all stitches to smooth out transitions. Continue in stockinette stitch until the total length from the brim to the top edge is around 7–8 inches.
Finishing the Bonnet: