I'm in the mood for WDW... Simply because it's a day that ends in Y!
I usually start planning my next trip as I'm leaving from my previous one, which can be a year or 2 away!
I start by reading just about every guidebook I can, cover to cover. This site and other site searches help keep me on track too. I usually have Disney music (from parks and movies) playing all the time.
One of the things I do in advance is make a list of things I'm going to take with me. That way, I can stock up on things early when they go on sale/clearance, if I need anything.
I also start walking for at LEAST 1/2 an hour a day. Got to get those feet in shape for all those miles I log at WDW (my hubby and I have logged 10-13 miles in a single day before!)
I also start a movie marathon, boning up on all my movies or watching the Disney Channel in my spare time. I really turn it into a project! I love planning/dreaming way ahead of time. It makes it all the sweeter when I actually get there! :sohappy: My plans usually change quite a few times between now and then. I'll re-write them as many times as I need to. In the end, they just become "guidelines" anyway and we usually use it as a skeleton to build the memories which are the meat of our vacation.
I also get a calendar and start writing on a daily count down in my own special style. See, for me, you don't count the day you are currently living, becuase you're in it. And you don't count the day before you leave, because that's called "tomorrow", so my count down is always just a "tad" shorter (or feels it!).
Have a great trip guys. I won't be there for over 400 days still.