Rectangle Hat
This is the probably the simplest and easiest hat there is. Why probably? Well it kind of depends if you prefer sewing to decreases. The idea is simple: knit a rectangle with a length that is a bit less than the brim of a person's head and a width that is a bit larger than its depth. Sew the shorter sides together, making a tube/cylinder. Thread a piece of yarn through the top and pull in such a way as to close the hole. Tie it. Weave in the any ends. You're done. The resulting hat is usually much better looking than one would guess from such a simple procedure. Now the non-trivial part is of course to calculate the length and width of the rectangle. Here are some ideas. Length: - measure the circumference of another knitted hat you may possess, or - measure the head's circumference and subtract about 1in/2.5cm (this is because the knitted fabric is stretchy and you don't want the hat to be too loose). If this hat is for a small head, like a baby or child, ...