I've tried many different things and this is what works best for me. Not everything that works for me will work for you, some people are better at taking faceoffs in different ways than others.
1. Watch the puck as the ref drops it, not as it hits the ice. This is more important if he is dropping it fast. If he is dropping it slow this might mess you up a bit if you are just playing hungry hungry hippos once you get the green light. Work on your timing if this is the case.
2. Widen your stance dramaticly and get close to the ice. You don't have to look like
this, but those are NHL players, so they must be doing something right. This advice helped me in ways that I couldn't imagine, and now I don't understand why other people don't do this. If you remember anything from this post make sure it's this tip.
3. If one guy is giving your trouble, try a different approach. It boggles my mind when I see somebody lose one hundred percent of their faceoffs to a player. There is a way to beat everybody, if what you are doing isn't working, try something else like winning the puck on the forehand if you primarally take faceoffs on the backhand.
This is by no means all my stuff, but if I were to get into it I could probably write a book on winning faceoffs. I suck at most other faucets of ice hockey so I take a lot of pride in my ability to win a face off. These tips SHOULD be able to help you but some people are better sticking to thier own set of rules. Try to develop a plan that works for you when lining up. Hope this helps.