You need a minimum amount of karma to create a poll. If you search you can probably find an estimate of the required level, I don't know it offhand. Then you can search for how to create a poll (probably the same search will give you both answers).

Edit: Here's a start:

https://news.ycombinator.com/item?id=3380115

Edit: I don't know why you were downvoted, so I upvoted to compensate. It's a reasonable question, although it is answered by doing a quick search.