Please note that the following information is best applied at and most useful in Magic Kingdom. The other three parks have both tiering systems in place limiting which FPP guests can get and when, as well as fewer attractions that actually utilize the FPP system. You may have some success in those parks, but you’ll have the most success using this plan in Magic Kingdom.
Now, sit back, relax, and get ready to have your mind blown
Guests at WDW are afforded the opportunity to pre-book up to 3 FPP experiences prior to arrival. For guests staying onsite or at one of a few Disney Springs area affiliated hotels, this can be done 60 days in advance for the duration of your stay for as many days as you have park tickets linked to your My Disney Experience account. For guests staying offsite, this can be done 30 days ahead of time, one day at a time, for as many days as you have park tickets linked to your My Disney Experience account.
After a guest has used these first three pre-booked experiences, they are entitled to book more, one at a time, for as many experiences as they can get until park closes or until they leave for the day. This fourth-and-more option is one reason it is smart to book those first three as early in the day as is reasonable. I prefer to book mine beginning about 1 hour after park opening since the first two hours are generally lower crowds and a lot can be done without requiring FPP. My intent is to use that first one at the end of the one-hour window, with the second one booked right on its heels and the third one at the top of that next window. My morning would look something like this:
0800 Park opens
0915 First FPP is booked (good from 0915-1015)
10:10ish That first FPP is used
1015 Second FPP is booked (good from 1015-1115), and used as soon as I am done with the attraction from the first FPP, somewhere around 1025
1115 Third FPP is booked (good from 1115-1215, with plans to modify. Keep reading
That third one is where the fun begins. As soon as you tap in for the second one around 1025 and are awaiting your ride, get in your MDE and access your FPP plans for the day. Select the 1115 FPP and choose “Modify”. Select a time that is sooner than the original 1115 window so that you can ride sooner. Hopefully you can modify it to around 1030. Now you’ve done three attractions using FPP in under an hour – 1010, 1025, and hopefully 1045 or so.
Once you tap in for that third one, go back in to your MDE and book a fourth one. Take any time offered for the attraction you want. Save it. Then, go back and modify as you did with your third one, bringing it close to when you will be ready to ride rather than waiting. Where desired, or when necessary, book the subsequent FPP for right after a ride/show/meal/parade/other diversion is complete. You’re then “waiting” while you’re doing something else you planned to do that day, but you’re not wasting any time in line.
Lather, rinse, repeat.
The end result is that you basically show up and go from ride to ride without waiting (much) at all.
We did a total of 9 Fourth-and-beyond FPP one day at MK on what felt like a crushingly busy day. We had things we wanted to do but no firm TP that day. We decided to see where the FPP took us - and after tapping in we (ahem, I) grabbed the next one and the next one and the next one… everything we did that day was effectively a walk-on. We were able to get back to back times for nearly everything and with minimal backtracking (I don’t see the point in that - we walk enough at WDW!). Average wait time was definitely not more than 10 minutes of true waiting on that day.
The exception to this plan is FOP, where it is difficult to get a FPP or to modify whatever you do get. If you wind up with a late-day FOP, keep it and consider showing up an hour before RD to ride with a very short or non-existent standby wait. One could argue that by arriving an hour before rope drop you are waiting. I’ll give you that. But you’re using your literal FREE time to wait so that you don’t have to use your expensive, paid park time to do so - so that while all the people who don’t know how to work it wait, and you walk on the rides in the rest of AK for a while.
Repeat after me: modify, modify, modify.