1. Get people to notice your slender hips

Keep your top as plain as possible. Save the ornamentation (if you must use any) for down below.

Drop waist skirts are a good idea. Sheath skirts with open back and shoulders are also a good idea.

2. Make your long legs stand out

Skirts with an open front slit, or short skirts (above the knee) all look good.

3. Minimize your shoulder area

Strapless dresses, lowcut in the back, spaghetti straps, and most open necks & backlines look good on you. Keeping your shoulders open also makes them look narrower. Keep the bust reasonably fitted. You may choose a sheath (tight around the hips) dress that shows your legs, or a slightly flared skirt that widens out below to balance your top. Short skirts look wickedly good on you.

4. In general

Most open top dresses are fine. Skirtwise, most things go. Only thing is, don't wear any that are too full or gathered at the waist. You will look kinda funny.