I'll assume that "spaced out" and "wall of text" refer to the common problem of how to space paragraphs. It's the same in F&W as it is elsewhere. Use the Enter button twice to make a new paragraph, since the tabbed paragraphs that you would have in Word (or similar programs) won't carry over.
What I guess can be called a "mandatory style" is just make it easy for people to read. Space your paragraphs, don't change the font too much (especially the color, as Syd said, since there's so many skins on this forum), and just use proper grammar to the best of your abilities. That's really it.