When are you planning on going? There's really not much you can plan/book yet since the dates are so far away. But in order:
1. Choose dates
2. Choose lodging
3. Choose how many days you want to spend in parks (I would do no less than 5-6 if possible, which allows a full day for HS, AK, 2 days for MK and 1 or 2 full days for EP)
4. Start looking over the rides, shows and restaurants available at each park to get an idea of what you want to do.
That's really all you can do this far out. As it gets closer (6-8 months away):
4. Start looking at crowd calendars if you want, to decide which parks you want to visit on which days.
5. At 6 months out you can start booking your ADRs (dining reservations)
6. Book your FP+ (you can do this at 60 days out if you're staying on site, 30 days out if you're staying off site)