This blog post details how to submit enhancement requests, and vote on enhancement requests submitted by others.
The link for this is in the footer, on the far right. Find the link and click it.
Review, submit, vote
To vote on an enhancement request, you must first View it using the button on the right.
To vote for an enhancement request, select the up arrow. Once you do so, you will see a down arrow, which you can use to retract your vote.
To add a new enhancement request, select the button: Add a New Enhancement Request.