When you click on "Post New Thread" there's an option near the bottom that asks "Poll or no poll" or something like that. Make sure the bubble box thing is checked and enter the amount of options you want. Then submit a new thread. Instead of going to see your new thread, you're taken to another screen that allows you to insert the options for your poll. Do so, and then hit done or submit or whatever it is, and voila! New poll.