Here's a picture from one of my current projects. On this outdoor patio we used a monochromatic gray palette. Using different shades of the same color keeps the area simple and allows the surrounding elements to be noticed. For a pop of color we have set purple hydrangeas in glass jars. They add intersest and texture to the space and give a hint of whimsy. The neutral backdrop also brings the simple greenery behind the lattice to life!
You can apply the same concept to clothing. There are a couple of gorgeous pale grey dresses available from Fernanda Carneiro right now on Badjoan.com. The Strapless Dress with Screenprint or the Colorblock Dress with Ribbon are both a light and neutral shade of grey with black accents and purple undertones. You can add a pop of color with the Rich in Friendship Large Faceted Earrings in Purple and then finish off the look with an earthy element by adding the Beth Springer Long Clutch in Olive!