When you're out all day, you need to re-apply your sunblock a few times. Skip the little travel-sized ones and get a big tube so you can slather it on.

I like to carry wet wipes or similar in my handlebar bag. On tour you end up doing lots of dirty things with your hands and then later eating or drinking. E. coli will end your tour real quick.

After you're done riding for the day, consider going commando so everything can air out. I usually pack a longer skirt for this reason.

Don't worry about your hair. You'll come home with awesome natural highlights.