I feel best in skinnies and a boxy sweater.
Dresses - I keep simple. Last summer I wore a couple of very short A-line ones, like Goat do but cheaper versions. Sort of 60s style shape, with boat neck. Also like same but 3/4 length sleeves or cap sleeves, but for me the key is plain colour, slash neckline and v short.
It's simple, clean and works with statement sunnies and a crossbody little bag, so similar in vibe to the skinnies thing.
No to prints (unless stripes), scoop necks, defined waists or below the knee. Although maxi can be good, I got a lush one from Gap last summer that's basically a floor length grey t-shirt, clingy and in softest jersey. Just add sandals, cross body mini leopard bag and sunnies 
Zara usually do good dresses in short, simple shapes.