Be detailed. The more details you specify about the question, the easier it is for other people to answer.
Remember that the folks reading your question do not know your environment like you do. We only have the information you provide to help us formulate answers.
Don't be afraid to edit your question to be clearer. If you think the question is confusing, edit it for the benefit of the readers. Maybe by changing the sentences, other people can understand what you are trying to get at.
Show us that you are applying our answers, even if it was wrong. Assuming you have tons of answers. You try each one and all of them failed. You should let us know (either via the question or via the comments) which one failed and what are the results.
Treat the readers with respect. Assume that they are not idiots. You show us respect and we will show you respect. Be arrogant in your questioning (although usually, this isn't intentional) and we will not respond.
Don't be afraid to show the things you did wrong. This would either save us time in responding with the same wrong answer you came up with and it would show us that that you researched the problem before asking us about it. Note: Alternatively, it's understandable if you don't want to include your experience in doing something stupid which caused the problem to get worse. Discretion is advised.
A good question should tell us the following:
- What are you trying to do?
- What have you tried to make it happen?
(or what you are considering trying if you're asking for advice on a plan)
- What did you expect to happen?
- What actually happened?