6. Understand The Tier SystemFastPasses are reserved through the My Disney Experience mobile app. You may reserve 3 FastPasses per day in one park; after you use all 3 in the park, you may reserve additional experiences one at a time, and yes- it can be in a second park if you have a Park Hopper pass. After you use your 4th, you may book a 5th, and so on. Keep in mind that your FastPass windows are 1-hour in length, and they cannot overlap (check out # 2 for an advanced tip related to timing).
Most of the parks have a Tiered FastPass system. In each park with Tiers, you can choose only one Tier 1 attraction; the other two choices must be in Tier 2. At Hollywood Studios, the 3 attractions in the Toy Story Land are all currently listed at Tier 1. Note: The Magic Kingdom, despite having the most FastPass+ options, does not use a tiered system.