A denim jacket is a must-have. They can be worn with almost anything. I have seen denim jackets worn with long knit skirts, over leggings, even over sheath dresses; topping a casual business ensemble.
I did notice that the price range for these jackets is quit broad. I have seen them for as much as $80.00 in regular retail stores. You do not have to spend that much money. All of mine come from thrift shops.
Wear yours over a pair of white jeans or a long white skirt. I have seen them worn over long flowing knit skirts and sheath dresses. Make sure you roll up your sleeve for an extra chic look.