My dad only likes hats with folded brims, so I’m doubling the ribbed section (ugh) so the brim doesn’t cover the colorwork.

Size 5 for brim, size 6 for stockinette, and size 7 for colorwork. (Always go up a needle size from solid stockinette to colorwork stockinette - otherwise, the colorwork will be much tighter than the solid sections. On a hat,this gauge change is especially noticeable since the colorwork is usually on the largest part of the head.)