Here is a crocheted hat made from the 15 january 1934 "penelope" (a french magazine, I had laying around ^^) :
The process is quite easy. Start crocheting a rectangle in treble stitch : 28 stitches width x 41 rows = 13 cm x 44 cm (44cm or more accurate your actual head size). And another one still in treble stich : 8 stitches width : 4 cm x 25 cm long.
EDIT : crochet size : 3,5
Close the biggest rectangle in sewing one side :
Close the top edge of that tube (gather a little bit) :
Add the small rectangle at the top (gather a little bit also). It's finished !