First some yarn info: I used Debbie Bliss yarn, called Merino Aran. I got it in a sale, and it has now been discontinued, and I don’t think there is an equivalent. It is not to be confused with her Cashmerino, which is softer and lighter. This Aran yarn is pure wool and quite thick, and is known as “aran weight”. But really you can use whatever yarn tickles your fancy, just that the sizing might be smaller if you use a lighter weight yarn.