Sewing a cinch strap on a hat

I would just get a piece of grosgrain (or ribbon) 1/4" or 3/8" wide and maybe 18" long, a cord lock and a small bead. String the bead on the grosgrain and then put the cord lock on both ends of the grosgrain. This should keep the cord lock from slipping off. Melt the ends of the grosgrain a bit to keep the ends from unravelling then sew each end to the hat just as you would a button. You can get the grosgrain (or ribbon) along with a bead at most any craft store.

Jennifer,

I have a lot of MYOG supplies lying around, including stuff you could make a chin strap out of. Just give me a PM with your mailing address again and I can send it out to you..you're gonna have to hand-sew it yourself though!

I have a hat with chin strap – just poke a hole on each side, thread through nylon cord through one hole, around outside brim to otherf hole and back through

My hat has grommets but that's not necesary, small hole shouldn't leak rain water so much

Is that a tilley style hat? If so the way tilley does theirs works well not sure where to find the small metal grommets but ive never looked, bet a hobbie or craft/sewing shop would have them. The strap itself looks alot like some shoelaces ive seen