Both of the above suggestions will work ... I prefer the MGM route when hopping. However, I thought I'd just mention that you can't take a bus from Epcot to BWV. There aren't any.
If you take a bus to Epcot, you will have to walk through Epcot (using a park ticket) and walk out the "back door" in World Showcase. From there, it's a short walk to the Boardwalk. Just FYI if you don't want to use a ticket, or you're planning to go to another park and don't have the hopper option.