Why not wear cotton? Synthetics (plastics) are bad for the environment and I try to switch to natural fabrics as much as I can. Maybe silk underwear to wick moisture away, and a silk neckerchief ( http://www.jinglebobs.com ). How about some linen garments and bamboo fabric?

Cotton wide brim hat, boonies or I don't know, Tilley if you are over 50 years old and you're willing to spend the money.

Sunglasses. Maybe the bayonnet temples if you plan on wearing helmets. Like the AO Original Pilots.

Poplin and broadcloth long sleeve shirts, like in bright blue, white and ecru, tan, khaki and even pink. Their plain tight weave cut the wind slightly more effectively than Oxford and pinpoint cloth although they breathe slightly less, but they work better as temporary floating devices and are versatile when you are layering since they are so thin. Some more casual shirts come with roll-up sleeves and tabs as a fashion statement but kind of functional too...

Tropical weight wool gabardines, super 100's and the like...

Stick with wool socks regardless of the weather.

I guess good high boots are important to protect against rattlesnake bites (make sure that fangs can't penetrate, i.e. snake proof boots) and scorpions (I don't live there, I'm just guessing) but anyway, never walk with open toed shoes for sure...

Frankie