How exciting! I usually spend 3 weeks wondering if I chose the right hotels and change my mind about where to stay, but you probably won't do that, so.......
Make your packing list. Practice using the app and keep an eye on wait times to get a feel for how they might be while you're there. I went through menus and made a list of things to try, made myself a list of where the water fill stations and good bathrooms are etc. Plan your outfits. Is there anything you need to buy for the trip? Hats,
cooling towels, new backpack, lanyard, pins etc.
Bask in the fun of completing your planning! Your trip will be awesome