Here are some common pbp (play by post) practices:
Regular plain old text is mainly used for narrative
Quote:
Birbo jumped out of his bed; cold sweat was visible on his forehead
Bold text ( coloured or not), is usually used for character direct speech, either in quotation marks or not.
Quote:
"Bloody hell!" he exclaimed.
What's all this ruckus?! Italics are usually used for character thoughts, again with or without quotation marks.
Quote:
"Must have been the wind..." he rest his back against the bed's headrest
or at least I hope so.