*update*: the hat was knitted without a pattern. i knitted a green hat in rounds (30 stiches/needle). at the beginning: one round knit, one purl for the brim (a turn-up-brim). later: knit the last two stiches on every needle together every third/second/every round.
earflaps: turn the brim up, then put 20 stiches for the earflap with a crochet-needle on your knitting-needle.
eyes: you will need four crocheting-rings (i don't know the english wort for it... prym plastic rings). crochet around two of them with white yarn. the green part of the eyes you can work this way:
the pupil is a black wood-bead.
needle: 3,5 mm (10 mm = 1cm; 2,54 cm = 1 inch)
if you have any questions, i will try to help you