When I did my San Antonio trip I took a piece of paper and walked around the house. In the bathroom I added personal hygiene items, Q-tips, nail file and nail clipper etc. i thought about my daily life and what i used. When I remembered something I would add it to the list.
Moleskin or bandaids for blisters.
Snacks to munch in the day for some energy. I like one brand that is 140 calories. No raisins though.
Zipper bags are important. The extra large can hold dirty clothes. Small and medium are great for messy foods or for sharing popcorn. You can dump the popcorn into one or more baggies and munch as you are walking then zip the bag and ride.
Talcum powder because of the heat. The baby center sells a lot of powder to adults.