I developed a "winter uniform" many years ago. I typically have on a pair of khaki pants and a cashmere turtle-neck sweater. I have them in a dozen colors, but usually choose a neutral color until it's coat-season when I like a see a bit of color at my neck from under my coat. I wear Belgian shoes (have them in tons of colors) unless the weather is bad when I wear my Stuart Weitzman faux Belgians. I always wear jewelry - a nice heavy gold chain necklace, big gold bracelet, a ring (have lots from which to choose), and earrings. Sometimes, I'll wear a pair of grey flannel pants and I'll choose dressier earrings (I adore shell earrings and have 3 pair) and an Hermes scarf - for going out to lunch or shopping in stores were I need to look more pulled together. Since 1985, I've carried a Vuitton monogram bag.
Summer is linen blouses and pants, Lily Pulitzer-type prints, needlepoint shoes or Belgians, my jewelry and a Nantucket basket I inherited from my mother-in-law (yes, it's the real deal).
I'm heavy so I have to make an extra effort to look tailored and classic and pulled together. When one is young, slender and beautiful, anything goes!