Each bus will go to a different park. They will be very well marked. They are like the city public transportation buses but are new, clean and pretty comfortable. AS SPorts is supposed to have very good bus service.
At the parks the bus station for your resort will be clearly marked. It may not be the same spot you were dropped off since the drivers usually pull to an open slot for drop off. Your pick up slot may serve more than one resort, but the buses are clearly marked as to which resort they are going to. It's very easy.
Besides saving the money for a rental car, and not having to deal with the aggravation of driving in Disney, the buses offer another benefit. If you drive to MK you park at the TTC and then take the monorail or ferry to the MK. The Disney buses drop you off at the front entrance to the park. Time wise, I think driving and busing are equal (others may disagree). While you may have to wait 10-20 minutes for a bus, when you drive you have to walk or take a tram from the parking lot to the front gate (or monorail if going to MK).
The buses go directly from your resort to MK, Epcot, MGM, AK, BB, TL, and DTD. Sometimes the bus may go to a park and a water park on the same route, but, again, this is well marked. The buses do not go from resort to resort. If you want to do some resort hopping you need to take a bus from your resort to the nearest park and then transfer to a bus going to the resort you want to see or dina at. After the parks close at night you can use DTD as a transfer point. It takes a little time to get to DTD. Some people prefer to take a cab to DTD to save time.
I have one question: how are you getting from the airport to Disney. Mears is cheapest, especially for only one person. However they iften stop at other hotels along the way and could take a little longer. A limo will take you directly to your hotel, but will cost considerably more (I think in the area of $60-80). Don't know what your
budget is like.