I don't know how many people have done these, so i'm just going to do a basic overview.

a shared story is one that people collaborate on. kinda like a role play, but you get inside the heads of all the characters. and, because i moderate this forum (right now) and not the role playing ones, i'm going to lay down some shared story guidelines:
people can write as much as they wanted, but i will put in a minimum: everyone must write at least a paragraph, which works out to at least four sentences. dialog counts as a sentence. so, if you have 4 lines of dialog, that counts. there is no maximum, but don't kill the story! oh, and please make an effort to make this a good story, as in, take care with spelling, punctuation, grammar... basic stuff. and please try to keep it making as much sense as this kind of story can. easy, right?

~Queen of Angst