Dear Young Professional:
Every Thursday the New York Times has a section on Styles. Today's (February 23, 2012) lead article is entitled "How to Wear A Tux". Within the article is also a discussion of how not to weat it.
If you can access the article, either in hard copy or from th Web, you will surely enjoy it and may even find it helpful.
Remember, dress with class and
Keep smiling
Harv