We prefer to take the South exit from the airport and follow Route 417 (aka the Greenway). You will encounter two tolls of $1.25 each. There is a cash lane on the far right (it looks like an off ramp) and it is manned so you don't need exact change. Get off at exit 6 and follow that road straight onto WDW property. After the welcome arch, take your second right and then quickly get into the left lane so you can turn left at the next set of lights.