I've Learned at Faire 1. Always wear sunscreen on all exposed areas. Even if it's overcast you can get sunburn. On hot days drink plenty of water. You can get dehydrated quickly being in the sun all day.
Baby powder is great.
Use anywhere you get hot and sweaty. It will keep you cool and dry. Hats were very popular, take advantage of it if you can. Click here for more details. I hope you enjoyed your stay.