I also wear my hat while gardening, a nicely woven straw that helps my head breathe. I also make sure to put some cream on my face with UV protection, just because it is so dry outside. Then if is is so warm and I don't want to dab lotion on my arms, I have this long cotton gardening mittens that goes from the cuff all the way to my upper arm, so I can have some sunshield.
Oh don't forget to wear safety goggles/eyewear while gardening...soil might hit your eyes..or nasty bugs..
