State the problem as simply as you can. Don't think too hard about it. Just write it on paper.
Answer the following questions about the problem: who? what? when? where? why? These are sometimes called the five Ws, and they can help you describe the nature of the problem and its effects. Try to be as clear as possible in your answers. Also consider the question: how?
Rewrite the problem statement based on your answers to the who, what, when, where, why and how questions. This rewritten problem should be fact-based and stated as clearly as possible.
Determine the end result you would like for the problem. Don't worry about figuring out how to get to the end result. Simply imagine the future state that you desire on this particular issue, and write it down.
Answer the following questions about the end result: who? what? when? where? why?
Adapt your problem statement based on the desired result. The statement shouldn't suggest a solution. Instead, it should clearly flesh out the problem in light of the end result you desire.
Edit the problem statement, trying several drafts. Try to limit it to one or two sentences in length. When it's complete, you'll have a problem statement that clearly states the problem and leads to effective brainstorming for possible solutions.