If you have a valid reason for a poll, you simply check off the Yes box below the thread text box in the "Post a Poll" section, and change the number of poll items to the number you will have in your poll (you will have an opportunity to change that so you don't have to exact in the first go).
Fill in the thread text box with the content of your first post that will introduce the poll, and fill in the thread title (do not add the word Poll, it's automatically added to the title). Then submit the thread.
The next screen is where you fill in the options, the poll question (can be different from the thread title), and select the various attributes of the poll. Be sure to enter the number of days you want the poll to run. If you don't fill that in, it will run forever which makes no sense for a poll. Double check the items to be sure they are as you want them, check the spelling, etc. Submit the poll and you're done.