You'd have to wait until Epcot opens at 9:00 a.m. (Although World Showcase doesn't open until 11:00 a.m., you're allowed to walk past the UK and Canada to Furure World.) You'd have a fairly long walk through World Showcase, Future World, and out the main exit to the Epcot monorail station. You'd take the monorail to the Ticket and Transportation Center, where you'd have to transfer to another monorail or to a boat.
I'd recommend the bus, which takes you to the bus center near the front gate of the Magic Kingdom.