If you're after a laid-back but also seriously stylish outfit, try teaming a grey coat with a black bodycon dress. Black suede over the knee boots finish off this outfit very well.
Black Bodycon Dress with Grey Coat Cold Weather Outfits
A grey coat and a black bodycon dress are absolute staples that will integrate perfectly within your casual rotation. If not sure about the footwear, go with a pair of red suede over the knee boots.