One of the questions was about preventing blisters... I carry a bottle of New Skin with me in the parks. I only wear a fannypack/hip pack that has enough space for my cell phone, ID, water bottle and the new skin. I have a little bottle of sun screen on a clip that clips to the pack.
The new skin can be used for preventing blisters from shoes that might rub, and also used after you get a blister. The product DOES sting when applied so little kids might not like it, but adults can deal with it.
As for shoes, i bring a couple different shoes with me and i often change through out the day (i often go back to the hotel or keep a change of shoes in the car). I may wear flip flops made by either Teva, Sanuk, or Reef. i will wear sandals made by Keen. These DO rub my feet (although not as bad as when i first bought them), so i often wear them with a thin set of socks that are in funky colors or patterns. The socks basically blend with the sandal so it does not look like i am wearing black socks with sandals.
For Tennis shoes i generally bring 2 different types. 1 is a set of merrells that is made with a good deal of air mesh that allows air to pass through easily. the other shoes will be one of my barefoot shoes. They dont provide much padding and on hard ground all day they could hurt, but if i am just doing a short outing, like going to downtown disney, i will stick these on for a while. I used to have bad hip and knee pain, but that started to go away once i started wearing vibram 5 fingers. They take a while to get used to, but they also helped correct really bad hammer toe.
For dress shoes, i generally have 2 options. I have a set of flip flops that are a little dressy that often work with many resort outfits that are a little fancier. I have a pair of dressier wedge sandals, i think merrell but i would have to double check that have a shinny silver color. They are comfortable to walk in and dressy.
If i am wearing a full length gown (for Victoria and Alberts) i hemmed my dress so that i could wear flats (ballet flats). After twisting my ankle and falling in high heels, i just cannot get into high heels anymore without a very painful ankle.
I also use baby powder (i like the lavender scent) in my shoes and also on my body to help keep me feeling cooler and fresh during the day. I will sometimes wear silk wrap dresses. They stay cool and are pretty and can be dressed up or down depending on the day.
I will wear mineral powder on my face that helps with both sun exposure and i also thinks it helps me to look less sweaty.
On a side note... in the past i would wear sketchers or addidas and in the end, they would make me feel tired, i think because they were heavy shoes. sketchers has recently come out with some super soft and light shoes. I have not tried them on yet so i can give no info on them, but they might be a good option.