I didn't read through everyone's post so I'm sorry if this is repeat
I knew this for our last trip but I didn't a few years ago---you can get a free glass of ice water at any counter service restaurant. We carried an empty bottle of water with us, and just went up and got free water and dumped it in for easier carrying. We just got back from a trip last week and I saw so many people buying bottles of water. I know some people don't like the taste of Florida water but it didn't bother us at all----free is hard to beat!
We get the cheapo ponchos and carry those around with us that way if it rains, you can throw them away after you are done and not have to worry about carrying a wet poncho around.
Don't get too stressed out! Just go and and have fun-- so many people have a huge list of must haves and you just can't do everything. Make sure you take time to relax and enjoy the parks! There are so many beautiful things to look at, if you are just running around like crazy, you miss so much of what is Disney!
We wear Keen shoes. We like them because they are comfy and if it rains, we don't care if they get wet. and we don't worry about wet socks and sneakers. if you do wear sneakers bring another pair of shoes to wear the next day in case they do get wet because they probably won't dry. Also bring band aids and or moleskin to apply if you get a blister. Mine wouldn't stay on all day either so I had to put new ones on.
If the nightly shows are important, make sure you don't arrive 5 mins before and expect to get the best spot- if you want a prime spot you will need to come early. We like to use this as our rest time. If you don't care so much, there are a lot of places around the parks to watch that are just as nice
Sunscreen!!! put on throughout day-- if you have the spray kind---be nice to the people around you and step away from the crowd haha
Make sure to get a guide map every day and a times guide so you know what is going on and where you need to be.
Enjoy the resorts! take some rest time in the middle of the day and hit up a couple! They are awesome! and usually the best restaurants are in the resorts (or at least that is my opinion!)
Don't always be looking through your camera, make sure you enjoy what is going on around you
Don't feel you need to stay in a huge group-- split up! We went as a family a few years ago and splitting up during the day saved us from having arguments! It's hard to move around in a large group anyway.
above all---Have so much fun and make amazing memories!!!!! Take a deep breathe if things are getting stressful, find a spot to sit down, and just people watch until things have gotten less stressful. and I know you only asked for 1 thing butttttt I decided to go above that haha
Have fun!!! and congrats on the marriage---Get buttons at the parks to celebrate!