If coming via West Seattle, note that the Fauntleroy dock loads cars, buses and walk-on passengers going to both Vashon and Southworth. Be sure to say you are going to Vashon-- or give the "V" (peace) sign, which will load in Lanes 1 and 2. Lane 3 is usually (but not always) reserved for Southworth.
Friday evening traffic (Thursday if it’s a 3-day weekend) and Saturday afternoon (especially if there is a big event in Seattle or on the island) can be "heavy" with a two-boat wait from Fauntleroy, Point Defiance or Southworth, esp. from 4 to 7 pm.
Take a virtual tour of Vashon Island. Move your cursor over the various “neighborhoods” in this link and see the beauty and uniqueness of Vashon-Maury Island!