Welcome Back, Catherine!
Each of Disney's theme parks, water parks, Disney Springs, the Ticket & Transportation Center and ESPN's Wide World of Sports all have a single and centrally located bus parking lot. Where the bus drops you off is where you'll find your return ride. And should you wish to hop from one area to another, you'll be able catch a direct bus from these lots without having to first go back to where you started at the TTC.
Take a look at this webpage about
Disney's Bus Transportation. Scroll down a bit, and there is an interactive map that as you toggle between the different guest areas listed in blue it will zoom in on the exact bus areas of each location. Click the 'Magic Kingdom Park' listing and two pins will drop. The Ticket and Transportation Center is pin number 2. This is where your hotel bus will drop you off. Once at the TTC, you'll find multiple bus listing boards that will basically say 'Epcot, Bus 2. Disney's Hollywood Studios, Bus 5." and so on.
Click on the Animal Kingdom listing, and zoom out a click or two. You'll see four white buses near two long covered buildings close to the theme park entrance. This is where you'll be dropped off from the Disney bus you caught at TTC and where you'll go when it's time to leave. But, if you're not done with your Disney Day yet and you'd like to go to Epcot or you have a dinner reservation at a Disney Resort Hotel, you can catch those buses directly from Animal Kingdom, from this bus lot. When finished, you can catch a TTC bound bus from where you are up until two hours after the latest park has closed for the night. The only thing buses don't do is bounce between two resort hotels. You would need to transfer buses at a park or the TTC first.
~Kristen