By your early 40s you have a stronger sense of who you are as a person, and know the image you would like to convey to the world. This is the perfect time to articulate your style and invest in some classic wardrobe staples. According to fashion expert Stacy London of What Not to Wear, "There are three things always you should consider -- your body type, your age and your lifestyle." These factors help craft a wardrobe of pieces that fit your body and are both functional and flattering.

When heading out to shop for new wardrobe staples, make sure to try on different sizes and find what works best. Investing in quality tailoring will ensure each item fits you like a glove. Dress for your body by emphasizing your favorite attributes. Skinny jeans or walking shorts show off svelte legs, and silk or cotton tanks draw attention to toned arms. Always strive to bring your upper and lower body into proportion. Create that hourglass shape with closet staples like a fit-and-flare dress. If you're a rectangle shape, add a slim belt right at the natural waist for emphasis. Balance pear-shaped proportions by creating more volume with brighter colors and a wide neckline on top.

Your daily routine plays a big part in the types of items you should be putting into your wardrobe. If wearing a suit to the office is your norm, then create a traffic-stopping look with colorful pieces that mix and match. Pair your suit jacket with a striped A-line skirt and red pump with a wedge heel. For those who are constantly on the go, find a universally flattering bootcut jean or white denim pants. Dress things up with a shiny patent leather ballet flat and printed blouse or go casual with a V-neck T-shirt. Statement accessories are another great way to personalize your look -- think a chunky necklace or wide metal cuff.

Keeping structured items in your wardrobe ensures easy grab-and-go outfits. Versatile pieces every woman over 40 should have include a tailored blazer, a well-fitted pair of jeans, a versatile button-down blouse and a little black dress. Look for items with signature details that speak to your style. Instead of a black blazer, go for navy blue or three-quarter-length sleeves. Find the cut of denim that works best for your shape and buy a pair in classic indigo denim and black. Choose a little black dress in a timeless silhouette like a sheath and you'll wear it again and again.

While you should certainly flaunt it if you've got it, showing too much skin can appear trashy. Instead of a short skirt and lots of cleavage, play up your best feature. Micro-mini skirts aren't so classy after 40, but hemlines don't have to hit the knee either. Employ the fingertip rule by placing arms tight to your sides to make sure your hemline is at least to the point where your longest finger tip hits your thigh. Choose necklines that show just enough cleavage or a dress with a low back, but not both. Creating a subtly sexy look will turn heads in the right way.