Generally the same applies as with any other problem, you [ask a good question](http://meta.serverfault.com/a/3609/37681) that includes:

- What are you trying to do?
- What have you tried in order to make it happen?
- What results did you expect?
- What actually happened?

Where in step 2 you add something along the lines :

> I found `[link to this old Q&A]` that describes a similar problem  but that solution there is not applicable (anymore) because of `[reasons]`.

That generally prevents people from closing your question as a duplicate and shows that you're a professional that has done some research and/or tried a solution before asking the internet for help.