If you knit the scarf first you'll have gangs of fun and the hat will seem easy-peasy afterwards. This is a great play exercise (it originally appeared in a Nashua booklet called "Play"), zippy and witty. The diagrams/schematics are clear and very helpful; the colour choices virtually limitless; and the making very straightforward, once you get the hang of making the modular triangles. The hat is ingeniously constructed-- make sure your friends see it in process-- they won't believe what it will turn out to be. Gauge is over 2 x 2 rib, slightly stretched.