There's a FAQ on this, but to me it comes down to just one thing:
"consider the point-of-view of the potential responder, whose attentions you are (of course) trying to attract."
(1) Write a concise but meaningful title. I'm looking at a list of post
titles right now ... and, years from now, someone
else might be looking at titles, also. Therefore, make the title count. Don't say "I'm a newbie and I have a question." That's a waste of time and space. Instead, make the title be the post's first and most-important tag.
(2) Write an answerable question. The very first ¶ of the post should clearly express the question that you are asking, and should ask it in "answerable" terms. Subsequent paragraphs should contain supporting information. Source-code should be optional, stripped to the minimum necessary to express the problem, and enclosed in code-tags. The responder, having opened the thread based on the title, should immediately be able to comprehend your problem and what you have done or tried so-far. The responder, based on just this, ought to be
able to now respond.
(3) Wait a reasonable amount of time. It might take a day or three for a response to arrive. Don't pester. If the thread doesn't get replies, consider
appending another comment to the thread. This will cause it to re-appear in the list of "active threads."
(4) When the problem is satisfactorily resolved, mark the thread "[SOLVED]"
and close the thread with a brief summary written by the original poster (OP). Briefly state what solved the problem, how you finally resolved it, and how you knew that the problem was solved. You're writing for the
future person who, perhaps years from now and after you're pushing-up daisies (oops, too-bad about that bread truck, pal ...), will rediscover the thread.
(5) Don't "gut the thread." Don't remove the original content.
Strikeouts are okay, as are
"Update: ..." comments added after-the-fact to clarify "post #1," but don't eviscerate "post #1" even if you now feel
about it. Once again, "remember future-person." The total thread, when finished and long-forgotten, should still be a complete and useful exchange meant to be durable for years to come. (It will be ...)