Coloful, patterned shirts make mixing and matching so easy! My tshirt was a thrift store score and it has neon yellow, magenta, black and teal, so I just grabbed from my closet what matched it and was good to go.

top: BDG, thrifted (originally from Urban Outfitters)
cardigan: Target* 
skirt: Banana Republic outlet
belt: H&M
flats: Dana Buchman for Kohls 

*affiliate link