When you use the forums you take it on faith that there are many experienced IT professionals out there who are willing to take time from their busy schedules to offer free advice and support to you.
In todays world that is an amazing thing! So take just a moment to make sure that you can return the favor by helping all of those people to help you.

First off take a moment to search ITNinja, it may have already been answered.
If it hasnt been then ask your own question.
Be very clear in what it is you are asking, avoid generic terms like it and this. Be specific!

Example of poor question:

I have a software package that produces an error when I try to push it out to a client and wont install.

Better way:

When I try to distribute Adobe Reader X through a managed install to Windows 7 cleints I get error 1102.

You are much more likely to get an answer if people understand the issue. 

MORE INFO!

The more the better, follow a few simple rules.
If you are talking about a script always include the relevant parts of it.
When describing other issues screenshots are always a better choice than words.

And finally

When your question has been answered mark it as so.
This little gesture has the benfit of letting the community know that this questions contains a solution if they are looking for one.
It also lets techs and IT pros who come here to solve problems use the search by unanswered as in 

http://itninja.com/question/unanswered

Focus on questions that need answers.
It really helps the community and you dont have to be a black belt to make this contribution!
If you see a question that has been obviously answered mark it as so.