i went up to cape cod for a long weekend last month, and i tried to pack as little as humanly possible.  here is what made the final cut:

cape cod packing{from top center, clockwise:  billy reid men’s button down (also works as a beach coverup), j.crew pleated skirt (purchased for $20!), j.crew matchstick jeans (also $20), nike yoga capris and running shorts, 3 target cotton t-shirts, eres bathing suit, green anthropologie dress, gray isabel marant cardigan, 4 pairs of underwear, 2 sports bras, and 2 regular bras).  in the center is a pink equipment silk shirt.}

the clothes were chosen for their versatility and ability to make several outfits.  i.e. pink shirt + white skirt, black tee + white skirt, pink shirt + jeans + gray cardigan, etc.  one cotton shirt and the nike shorts/capris were used for sleeping, but could also double as activewear for outdoor activities.
cape cod shoesi wore the superga flats on the way.  the beaded sandals were for any slightly dressier occasion, and the flip flops were restricted to the beach.