Thanks for reading,
Well, I've tried sewing a bonnet, but it turned out to be disastrous! The cutting had gone wrong somewhere, and I didn't have the courage to do it again!
However, I did find some tutorials on how to sew a sun bonnet for a baby. You can check this link for more information http://pickupsomecreativity.blogspot.com/2009/10/pioneer-sunbonnet-tutorial.html. Hope it helps!!