Just type what comes to your mind. There is no need to spend time on imaginizing how it will show up later (and if it doesn't look nice it's probably not your fault, most often that's caused by a bug in the software).

Signing your thoughts might sometimes be a good idea, too. At least if you write in the first person you should do so.

Even if this is not the IRC or a Board/Newsgroup, you are really allowed to be talkative.

If you can't finish a text, somebody else may do it later. Don't care.

Please don't strip off text and comments somebody else has written, or create a new page and fill it with your own opinion. Also don't go around and annoy others; internet technology allows others to get your address.

Comments

If you choose to comment on somebody else's thoughts (or just to extend an existing text) it is sometimes a good thing to insert a horizontal break (-----) before you insert your additions. More important is to often insert your name before or after your comment.

YourName:
  ... your comment to the
  previous paragraphs ...

Doing so usually helps discussions look more alive, and the different opinions do not screw up or confuse readers.