I've done WDW many ways - from methodically doing every attraction to seat of the pants and everything in between. I'm a DVC member so I'll usually reserve rooms 7 or 11 months out.
But besides that, what works for me the best is:
1) Pick things I don't want to miss 7 to 8 months in advance.
This year I'm taking some noobs ("Kirk, party of 9!") so the list is rather long. Hoop-Dee-Do, Luau, Back-Yard-BBQ, IllumiNations Dessert Party, Pirates & Pals Fireworks, Royal Table, IllumiNations Boat Tour, Fantasmic!, Be Our Guest Dinner and all but 2 Character Dining.
2) Look at historic crowd data and plan the lowest or 2nd lowest park for the morning of each day. Sometimes I'll do Evening EMH but not in the AM.
Crowd Calendar
3) Make "Must See" and Hard-to-get reservations at 180 +10 days out. Some of these are Pre-pay so it gives me a chance to spread out cost. It also narrows the time windows to my choosing. Some of the more popular events are impossible to get otherwise.
4) Leave some flexibility in my plans. One event per day, sometimes two so we don't end up running from event to event and miss enjoying the parks
5) Now, use FP+ at 60 days out. Also includes buying tickets and/or passes which also spreads cost out.
6) A couple of weeks before check-in I'll purchase a dining plan using my Disney Vacation Account (DVA) which I opened more than 120 days previously. (See my cost savings strategy below.)
7) On check-in I'll upgrade my tickets to premium annual passes using my DVA and enjoy my vacation with very few additional costs.
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Discount strategy - the DVA and funding it:
DVA - You can open a DVA and fund it over time. For each $1000 that you spend towards a Disney Vacation (Transport, Resort, Tickets, Dining, etc.) more than 120 days after open you get a $20 gift card. (2%)
DVA
Funding it:
1) Open a Target Red Card - Free, gives you a 5% discount. Connects to your Bank Account like an ATM.
2) I used a discount gift card site to increase this 7% discount to about 12% but I don't know how long this will be available. Ask me offline if interested.