I like one of those visor type hats as the top is completely open and allows good ventation. Hats are very hot on the head, so get a real light loose fitting one and of a white or bright color (reflects heat, while black absorbs heat). And shades by all means.
You can use a bandana to cover ears and neck to keep them from sunburning. Knew a fellow that had to have part of his ear removed due to too much sun (skin cancer). So use a hat and cover ears and neck too.
Light, loose fitting long sleeve shirt for balds, hiking out in the open, etc----and also for before the trees leaf out. Once trees leaf out, you will be hiking on the AT under tree canopy most of the time.
Sunblock is good. So is chapstick. Lotion also good.
See you out there.:cheers
Maintain