Leave the sandals and sneakers at home. A hemline no more than two inches above the knee. This is your best bet for a well-varied wardrobe. Choose several skirts and pants in neutral colors. A coordinating jacket can complete the look when you need to be dressier.
Solid colors are easier to wear on a regular basis.
Always wear pantyhose regardless of the deep tan you've been able to cultivate for your legs. Mules and loafers are also easy solutions. Scarves can add a whole new look for little cost. As for jewelry, keep it simple. Add black pumps and a pearl necklace and you can go anywhere with confidence.