Beginning my Questionnaire

I am getting ready to begin designing my questionnaire for my poll. I have decided to focus this poll on the issue of global warming. I am going to be designing it around what people feel about the subject, if they think it is a legitimate topic, and weather it is something that we need to be focusing on right now. Some things that I am really going to be paying attention to when designing my questionnaire are: the correct formation of the questions, avoiding non-attitudes, and making everything complete as possible. I am planning on looking at some of the polls that I have already posted about and studying how they form their questions and how many questions are suffice.