I think the only things not mentioned above are the meta-rules:
Post in http://forums.sirlingames.com/t/post-here-if-youre-looking-for-a-play-by-forum-opponent/ to request or accept a game. Typically, each player will go to www.random.org and generate a random number between 1 and 100 (the homepage default), with the higher number going first.
The player who goes first then creates a thread, with a title in the format of:
{optional to specify “casual” - tournament games always start with the name of the tournament to differentiate them} {name of player going first} ([Spec]/Spec/Spec) vs. {name of player going second} ([Spec]/Spec/Spec)
The first spec (optional to put in [brackets]) represents the color of the starter used. For games using a mono-color setup, the specs are usually replaced with (Mono Red) or equivalent.
When the game concludes, a rematch may be offered/accepted in the same thread. Typically the player going first alternates, regardless of who won or lost each game.