In addition to those mentioned:
Before making dining reservations, look up park hours, extra magic hours as well as schedules for fireworks, parades, and other shows you plan to see for the week you will be there. This can vary greatly from week to weekand may help when planning ADRs
Purchase park tickets through Disney or one of the discount ticket brokers
Make arrangements for your pet if you have one
Transfer points from Disney Visa to Disney Visa Rewards Card (if you have one)
Order groceries for your room from Disney, Garden Grocer, or WeGo, etc.
Stop mail and newspaper
Be sure to bring your
DVC member card, annual passes or tickets, TIW card (if you have one) in addition to identification, credit cards and cash.
If flying, don't forget your airline tickets and put magical express tags on your luggage.
If a few days of rain is forecasted, you may want to purchase inexpensive rain ponchos at home rather than purchasing them at Disney