The Monorail is probably going to be the fastest, but if there is a boat right there and handy without a big line to board, that may be faster. As for directions, the Boat Launch will be ahead and a little to the RIGHT as you exit MK. The Monorail will be more to the RIGHT, but make sure you go up the ramp for "Resort Monorail" as there is the "Express Monorail" that goes straight to the TTC (parking lot) and does not stop at the resorts. They travel in opposite directions too, so the Resort Monorail will stop at the Contemporary, the TTC, and then the Polynesian. It may help to have a look at some maps to get a feel for it.