I think the blanket statement I give to anyone who 1st approaches me and says.... I hear your the person to talk to, I'm looking to book a trip to WDW is....
plan, plan, and plan some more. Read threads on here. I love Allears website too and I look around and read what the official WDW website has too for specific things.
Alot of your strategies will depend on what time of year you are going - offseason = less busy, less strategic planning. Peak season = more exact precise planning, and timing involved but longer park hours to fit those things in.
We pick a park, make an ADR for a sit down meal in the park we are planning on being in for the day. Other than that we tend to wing alot based on lines at the time as we go off season and have been fortunate enough to have low/no crowds, most of the rides were walk on. I ask the kids what "must" you do and make sure we fit it in somewhere along the way but we have skipped over and come back to it if the wait was longer than we wanted.
So after all your planning and planning and planning, you arrive in WDW. RELAX! You are on vacation, you will not do everything (best reason to plan a return trip!

), and most of the time the only person stressing out over missing the red telephone booth in England @ Epcot is you, the person doing the planning.