Knowing the vision of the team and actually believing in it is perhaps the most significant step towards becoming an effective leader. At the end of the day, leading a team means inspiring the trust of your team members. And the best way to do that is to prove to them that you believe in the vision.
What you should first do is develop a good understanding of what the vision is, and determine whether or not it's something you can live up to. Next, use every chance you get to "sell" that vision to the team. Show them that you live and breathe it and they'll eventually realize it's something to grab on to.