To add to the above:
Disregard many of the people who say you must do this or shouldn't do that. I made the mistake of confusing anonymous disboarder opinions and speculations with fact.
Expect the ordinary/close to nothing and be pleasantly surprised by better. Especially with customer service, the age of the grounds, closures, weather. Your experience has innumerable variables.
Be prepared for how overwhelmingly large the property is. Even after watching videos and studying maps it's really easy to get lost or confused. When there are not cast members visible for help I hop in the nearest foodline to ask. Figure those cast members will inform management that more guidance staff is needed. The app is helpful for directions too.
Security is serious business there. Transportation can be slow. Give yourself time. Take your original plan and reduce it for ease and relaxation-especially if you have children with you! It helps to know where transit is and how it works in advance.
Almost nothing has a price on it. They use colors.
Go where the crowds aren't, and ask questions. A lot of people don't know what they are doing.
Expect rude selfish people and have a plan for coping. For example, when people hog tables at establishments in order to have a view or seat for entertainment. We used a trashcan in MK as a hightop table instead and tried to laugh about it.
Take restaurant reviews/popularity with a grain of salt. Your impression/experience will vary based on the day, time, and what kind of food you are used to. (Those from places with limited options are likely to be more impressed, as are those with a more simplistic palate). Look at menus for pricing. Take advantage of reservations, mobile ordering, etc. I recommend Disney Springs for the most bang for your buck.
Relax and have fun! People on here can make it seem way too serious.
My most important tip is "Don't rush through the magic to stay on the plan."
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