I use an I and N hook to make these hats. However, because the pattern does not use a gauge and is measured to achieve the correct size, any size hook or yarn can be used. You will need one of the hooks to be a few sizes bigger to accommodate the triple stranding for the bow piece. You will need 2 different colors of yarn, contrasting colors work best. I prefer worsted weight, but again since gauge is not an isssue you could use any type of yarn really. GAUGE Not important, we will measure to acheive the desired size.