I'll try to post something tonight...
As for posting for other characters, I think it's ok to make them say a thing or two, but not anything very big or important and in any case it's always nicer to ask the other writer. So writing
"Good day to you, sir!"
my character said.
"Good day,"
your character replied.
"How are you?" asked
my character.
is completely ok. But I wouldn't write:
"Good day to you, sir!"
my character said.
"Good day,"
your character replied.
"How are you?" asked
my character.
"My day is absolutely awesome this far - my love agreed to marry me!"
your character said and smiled.
because that's sort of intruding on the other writer's domain. Mostly, you get quite far by using common sense and your gut feeling about what you would or would not like other writers to do to your character. Of course there's leeway with characters with currently inactive writers, but I guess that can be considered with the aforementioned "common sense".
One definite rule, I'd say, would be NOT MAKING UP OTHER CHARACTERS' FEELINGS OR THOUGHTS.
And of course, everybody here is willing to edit their post if their characters are misinterpreted, so I wouldn't think it's a problem. People have been mostly very nice and sensible this far. But thanks to
Durelin for bringing this up, especially if the issue was not clear to all writers.
(And I think we also all have different opinions, so don't take my words as the absolute truth!
)