This concise summary serves, under the form of a step-by-step guide, as a technical reference to current moderators (not only the diamonds, but also those who are voluntarily taking part of ensuring high quality among Super User), as well as people flagging and editing (even suggesting edits).
When is a question acceptable on our community?
While closing and flagging can become a habbit, remember that we are trying to help the user. Handling questions doesn't only imply closing and flagging those that you don't like; but should also involve leaving a note how a question can be improved when possible, or be improved by you to make it match.
Getting your first question closed/deleted on this site is not pleasant, please consider first to improve it...
Is the question within the scope of Super User?
Our scope is defined in What kind of questions can I ask here?, the essence is that questions that match that paragraph are within the scope of our site as long as they conform to the Terms of Service.
Unless a question clearly matches one of the not about points of our FAQ, there is no need to migrate. In fact, before migration you should first ensure that the question is of sufficient quality: Don't migrate crap.
Is the question constructive, real and useful?
What questions should I not ask here makes it easier to check this out:
You should only ask
practical, answerable questions based on actual problems that you face. Chatty, open-ended questions diminish the usefulness of our site and push other questions off the front page.
The part in emphasis covers both "not constructive" and "real". Where as "too localized" is more based on how applicable the question is, because extreme conditions diminish the usefulness for everyone.
Keywords like better / best, favorite, good are good warning signs or a question being "not constructive", another sign is where someone asks to "recommend stuff" or "give me a list of stuff"; polling is not welcome here unless it is really niche.
This doesn't necessarily mean that you have the close the question for being subjective, you could turn it into a great question instead; see "Turn recommendation questions into questions that ask for advice".
Furthermore, questions should be about solving a problem and not about solving a task.
Have you thoroughly searched for an answer before asking your question? Sharing your research helps everyone. Tell us what you found and why it didn’t meet your needs. This demonstrates that you’ve taken the time to try to help yourself, it saves us from reiterating obvious answers, and most of all it helps you get a more specific and relevant answer!
Exactly, people need to do their homework because there is no point in doing their homework for them, questions like these aren't real simply because they don't learn them how to do it themselves.
Is the question a duplicate?
Duplication Question Suggestion Boxes allow you to see a list of questions at the top, allowing you to easily scan the list of possible duplicates and upon clicking the link it opens the close box for you.
Sometimes using a search engine could help as well. But remember that the main concern here is to prevent people from wasting time by not having them answer the question, it is not our goal to have all duplicates closed but if you want to try feel free to go ahead.
What can I do to improve the question?
Turning a badly written question into a question of high quality can help getting the question an answer, as well as making our site look better. The point of a Q&A site that can be edited is that you don't have to scroll through boring forum pages but that it takes you minimal time to read the question and answer, while learning the most out of it in the mean time. This is often summarized as Quality > Quantity...
Turn recommendation questions into questions that ask for advice.
Q&A is bad, let's go shopping outlines that while recommendation questions are not welcome, they could be improved by changing them to be asking for advice. While some questions are not salvageable, it is really worth it making an attempt to save questions who would result in really valuable advice.
Consider how "What do I need to consider when buying hardware to meet my needs?" is not constructive question and is instead extremely useful advice, not to forget that you can link to that advice the next time such not constructive question has been asked.
So, when you come across "Do I buy gaming mouse X or gaming mouse Y?", you know what to do...
Turning the title from a topic / task into a question about the problem.
Sometimes, the title of a question really doesn't explain its context.
Consider these three:
Force DNS Server
How to force DNS Server?
Where can I force a specific DNS server to be used on OS X?
The first one really doesn't tell me anything, the second one has the habitual "add 'how to' or 'how do I' in front and we'll be alright" behavior which adds exactly nothing. Both of these two are focusing on the topic / task / goal, but none of these two are about the problem.
Exactly, in the third one we get rid of the topic / task / goal and turn it into the problem which clearly lets you see that the user simply can't find the setting.
Here is another effective one:
Assinging MacBook Function Keys
How to assign MacBook function keys?
What do I need to assign a F1 - F12 key to a specific command on my MacBook?
Only the last one clarifies the problem, and is also more SEO-friendly as a side-effect.
Make the body easy to read
Removing excessive parts from the question as well as improving its look can greatly help:
Format the question with proper use of strong/emphasis/quotes/code-blocks/textual links/images.
Get rid of any spelling mistakes, make sure to use a spell checker / dictionary.
Enter is our friend, multiple paragraphs instead of a wall of text are preferred.
Remove irrelevant stories, paragraphs, "hello" and "thanks" parts to shorten the question.
Categorize the question into the right place.
Besides what's asked in the title, you can also help the reader by adding tags to the question. This allows the favorite tags system to function better, eventually getting the right persons to the question.
Make sure you add as much tags as possible, but avoid the use of meta tags.
Leave an edit note when an edit is not obvious.
While some edit actions in the questions are trivial, not every action would come over as clear to the poster. If their post is suddenly a lot shorter and you don't explain why it could be seen as an offensive action and/or confuse him. Not everyone reads the FAQ and/or Meta from start to end before asking their very first question.