Briefly, here's how I do it, for what it's worth. First make a table with the dates you will be there, and then, using the Info. on the Disney web site, write down opening times, parade times, show times, closing times, and extra magic dates and times for each park you wish to visit. Check Schlinger's Unofficial Guide, and write on your table the expected crowd levels for each day and each park.
Once you have decided on which park(s) on which day(s) based on the information on your table, you can proceed to make a daily personal plan for each park, using the park map to plan so that you do as little backtracking as possible, and, of course, including the attractions you enjoy the most. Think ahead when making your personal itinerary; for example, do not schedule a visit to a popular attraction that is near a large show just at the time the show will be ending and crowds will be exiting.
The next step is to make meal reservations and buy tickets as needed to make your personal itinerary work as smooth as possible.
Works for me.
Enjoy.