My bf's work Xmas party is next weekend. Since he works for an oilfield services company,(ie: redneck central- time to break out the "fancy" sweatpants) it is dressy casual. I'm a little bewildered to what this actually means but I think I want to wear my favorite black pencil skirt (Zara). What should I wear with it? I have a tendency to "over dress" so I don't want to over do it this time. Can I make it dressy casual?