It displays avatars of three players at once and invites you to vote for one of them. You then see a brief message telling you who has been notified of your vote. That can be a chance for you to find the real identity of a player. After you vote, another trio can be voted on.
At the bottom is a button you can click to vote for 25 of your sisters.
At the right is a list of players who have the most votes for the day.