The concrete5 forum is the obvious place to ask questions about concrete5. We are generally pretty friendly, especially if you are friendly and polite to us and put a bit of homework in to researching your question before asking it. To quote another C5 developer "If you expect me to put in some work answering your question, you're going to have to show that you did some work to ask it."
Provide as much information and investigation up front as possible, especially screen captures. That way, anyone viewing your post can easily see "Yes I recognise that issue and here is how to resolve it", which is much quicker than having to enter into a long string of Q&A posts to get the background before anyone can even work out if it falls into their area of expertise.
When a responder asks a question, please answer as fully as possible. If you don't give them the information they need, how can you expect them to help?
Don’t forget that many questions you may ask on the forums are already covered by the Developer’s Guide and by Howtos.
When you ask for help, and especially in your profile, make it clear what your programming skills and experience are. That way, anyone who answers can pitch their answers in a way you will understand.
Bear in mind that for most people, time is money. Both your time and the time of anyone answering a question. A good way not to get an answer is to ask a question that amounts to "I see there is an addon that does this. Rather than pay for it, I would like you to spend more time than the addon is worth posting how to do it here."
Stackoverflow also provides some essential guidance on how to ask questions on a forum that is equally applicable to asking questions on concrete5.
If your site is on line, remember to post a link to it, that way we can see what your problem is. Sometimes a site or the problem part of a site is not publicly on line, or maybe just viewing the site is not enough for you to explain a problem; that is where a screen capture can help.
A screen capture or screenshot is a picture of what is happening on your web browser screen. Using tools like "Awesome Screenshot" (see below), you can also add notes and arrows to explain your problem.
Attaching a screenshot as a jpeg or png to your forum post makes it much easier for others to see what your problem is and provide help, especially if you are not that familiar with all the technical terms. You will usually get better help more quickly if you attach a screenshot.
The easiest way to do this is to install a screen capture extension for your web browser. For example, with Google Chrome, "Awesome Screenshot" enables you to capture the screen, crop the part you want, and put arrows and notes on it to help explain.
Look for videos on installing and using it on YouTube:
Most web browsers have a developer console (though it may have another name like Firebug in Firefox). You can use the developer console to see what is happening inside a web page and what is coming to and from a web server. If you have a problem with missing menus or your site misbehaving after installing an addon, looking at the developer console will often help show what is going wrong.
On the forums, if you are missing a menu or your web site has locked up, the first thing you may be asked is "what error messages are in the developer console?".
Look for videos on using the console on YouTube: