I like this pin because it's a very serious portrait, but someone added graphics that seem fun and playful when they move; the opposite of the portraits tone. I think they go nicely together without overpowering both moods.
For a casual Friday, try RTR striped pants with my black nike sneakers plus a sweater on top. Or black nikes with Milly black pants and a top. Sweater: MKAO for Bik Bok // Shirt: Asos // Pants: Bik Bok // Bag: Steve Madden // Shoes: Adidas