My son (7 1/2) is on the higher functioning end of the spectrum and here are a few things that we do to make our
Disney vacations more enjoyable.
1. Like many others have said, a mid-day break is really important. We found that our son had a time limit on how long he could stay in the park and after that it all became too much for him to handle which lead to meltdowns. So, we always go back to the hotel after lunch for an hour or two of quiet time. He doesn't have to sleep (although his first trip when he was 6, he fell asleep every day and his second one when he was 6 1/2 he slept 2 out of the 4 days.)
2. We get him a GAC but really only use it when we need to. One of DS's triggers is dark, tight spaces so we use the GAC for rides like Roger Rabbit even when there is no real wait time.
3. We don't use a touring plan or a daily schedule. Instead, we give DS the map and he gets to pick where we go next. He really loves looking at maps and giving him the power to choose makes for an easier time. This will be the first trip that he will be tall enough to ride everything but the last two times we showed him the rides he was too little for before we got there. That meant that when he saw IJ, he knew he was not big enough so he didn't get upset that he could not ride. (He is FINALLY tall enough for IJ so he has picked that as our first ride this trip!)
4. I know that many people, especially those without kids on the spectrum, will hate this next one but we make sure we bring our son's Nintendo DS. We found that it really helped having the DS and especially the headphones for times when we had longer waits and bigger crowds than he could cope with. Having the game meant that we used the GAC for fewer attractions but at the same time we did not make life difficult for our family and for those around us.
5. Be flexible and be aware of the various triggers. I know that when our son gets hungry, he gets REALLY cranky. So, in my small backpack I made sure to pack a couple of granola bars. He's not a big junk food fan, so snacks in the park were not appealing to him.
6. We've never needed to use one, but I do know that some people like to have some sort of contact information on non-verbal kids. I've heard everything from temp tattoos to t-shirts to notes attached to shoes. I remember someone did recommend these:
Safety ID Straps
That's all I can think of right now! Feel free to pm me if you have specific q's I might be able to answer.