I blogged about this a while ago. The bullet points from that article:
- Read the question (carefully)
- Code is king
- Answer the question and highlight side-issues
- It's okay to guess, but be honest
- Raise the overall accuracy level
- Provide links to related resources
- Care about your reader: spelling, grammar and style matter
- A time-limited answer may be better than no answer at all
- Don't be afraid to delete (or edit heavily) useless answers
- Be polite
- Don't "answer and run"
- Have fun
(Obviously the post goes into rather more depth on all of them :)
You might also want to read the answers to this rather similar question.
