It is common on the boards to separate characters by color coding their speech. DM puts (not always, but mostly) NPC dialog in bold and some put different NPCs in different colors. Think on it as your "voice" - you don't have to see who's posting (username) or count on the post to contain the name of a person speaking (that is another be-nice-to-others) or even count on people who are in multiple adventures to necessary remembers who's who in which adventure. Pick one color and stay with it. Bold is optional.
Thoughts are in italics
I put all my dialog inner and otherwise in quotes, not everyone does - but living worlds had that explicitly stated so I got used to it.