Simple.
To create a poll, (1) Click button to post a new thread (2) Click the 'Yes! post a poll' checkbox at the bottom of the page (3) Set the number of possible responses you want to include (4)Finally when you click the submit button, you will be taken to the poll creation page, where you can specify the question and the list of responses you want to include.
Also, you can also specify a time limit for the poll. For example, it only stays open for voting for a week.
That's it !