For his bandanna, teal might be a fairly bright color in your area, but I would prefer a yellow hue. Also, I have seen bandannas that had useful information pertaining to survival printed on them. I don't know of a current source, but that might be a possibility....
Great idea Hikermor! I didn't want to discourage him last night, especially right at bedtime. I've got a brighter yellow one for him that I'll give him tonight when we repack his FAK. I'm on the hunt for one with first aid instructions or survial info on it. I'll let everyone know if and when I find one!