The Bunnies & Carrots hat is done in worsted weight and can be done in any size from baby to adult large, with or without ear flaps. If you decide to knit this particular hat, I have a recommendation. Start the ear flaps with your I-cord, then directly go from there to the bottom of the ear flap and then knit the ear flaps on the rim of the hat as specified. I made this hat for a four year old who managed to lose the cords to the ear flaps the first day he wore the hat so this method may help counteract that problem. In the photo above, the green hat was done in this method but the brown one simply had the I-cord cords attached to the ear flaps.
Also, don't strand the yarn between the bunnies because you will get puckering. This will result in some long floats but will look a lot better. You can tack down the long floats later if the hat will be for a child. If you hate bobbles (the bunny's tails are bobbles) you can double or triple your yarn and just do French knots instead. (Scroll down to yesterday's photo and look at the teal hat - I did the French knot tails instead of bobbles for that one only.)
I had some difficulty finding orange worsted weight wool yarn for the carrots - Nature Spun worsted from Patternworks is the yarn I finally used for the carrots. Cascade 220 also sells about three different shades of orange which would work for carrots.
I stuffed the carrots with plain old cotton balls and I only used one for each of these particular hats to speed up the knitting. The pattern actually has three carrots on top of the hat and one each at the bottom of the cords. Woodsmoke Woolworks also sells an absolutely adorable Bunnies & Carrots Hooded Baby Jacket pattern which I want to make also for the HRS to sell or auction off.