Human Go works best in crowded places. The first player marks the board with chalk or cordon, puts on a black hat, drops some further black and white hats at the corner of the board, goes to any intersections and sits down there.
For every turn, all stones on the board try to convince a passerby to join in, and the stones of the color currently playing give advise on where the new stone should place itself.
This really is great fun, you get to know a lot of people that maybe did not know Go up to this point, and it is a very new perspective to be a stone rather than see to board from above.
A variant is ActionGo.
--Pu der Baer
See also The biggest goban