To get some inspiration for off duty look, I went to (in my opinion) masters of that art. The ladies who normally totter around in perfectly put together designer clothes and get paid for it, the models themselves.
A lot of them have a fantastic style for after hour laid back look and here are some that I really like;
I particularly like Anja Rubik's look. Below is a combination of clothes to get the look - on the high street of course. She makes me wanna go blond!
BTW fantastic tan is obviously compulsory ;)