Skinny jeans is a very touchy subject amongst men. Some would rock skinny jeans and some would never. Many oppose skinny jeans because physically they bring about some complications. Remember that verse from Jay-z "I dont wear skinny jeans cause my nuts dont fit" (hahaha), well true enough skinny jeans tend to be a little bit tight on that particular area of a man's body. Personally I think rocking skinny jeans is a brave move for men, however the direction in which the fashion trend for men is heading skinny jeans will someday be the isshh. Swagger comes in very weird forms. If done right skinny jeans can be the ultimate swagger for men. And by right I mean a good mix of skinny jeans and shoes. The good thing about skinny jeans, they can be rocked nicely with both high tops and low tops, including formal shoes. Since skinny jeans are more punk-rock based, shoes like: Vans, Converse (Chuck Taylors), and Boots are more appropriate for a spot-on swagger. Here are some suggestions to learn from:
Skinny Jeans with Chuck Taylors. 
Skinny Jeans with Formal shoes/Boots.
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I'm not sure what you mean "formal shoes" but what I know is men don't wear formal shoes without a tux/dinner jacket. But have I seen people wore Dinner jacket and jean? Hell yeah. They just seemed to be all over the place. How do you really wear a patent leather shoes with a pair of jeans?Whatever floats your boat.