The most fail proof way to dress, whether it be in vintage or contemporary clothes, is to follow the classics like these:
The Little Black Dress

Image courtesy of Vintagevixen.comCalled the LBD for short, the little black dress is the go to item when in doubt about what to wear. I can be dressed up or dressed down depending on the accessories you choose. In addition to its ease of being a one piece garment, it is also in the most universally flattering color which also happens to be slimming as well.
To get the LBD right choose a simple shape from any era that has few decorative details to date it. Also be sure to stay true to silhouettes that flatter you body type. With those few things in mind you can look amazing no matter what decade you or your dress is from.
Though many of classic items are borrowed from the boys, the LBD is one is one style that belongs to ladies only.
Pearls
Pearls are the most versatile of all jewelry. They come in endless shapes, sizes, colors, and combinations that are easy to match with any outfit. Pearls are also the only type of jewelry that can be dressed either up or down and worn both day and night.
In vintage there is always great pearl costume jewelry to be had, just make sure to grab it if you see it, because you won’t be the only one looking for the most timeless fashion accessory.
Denim
Though the shapes and shades may have shifted over the years, denim has never gone out of style. A perfectly broken in and well fit denim jacket can be added to any wardrobe without conflict. As for jeans, find the decade who’s signature jean silhouette most flatters you figure, then keep your eyes peeled for the perfect vintage pair unlike anyone else’s.White Button Down Shirt
It may be a menswear staple, but the plain white button down is just as female friendly. You can get a white button down anywhere, but when you shop vintage you have all of its reincarnations at your fingertips. Dressed up or down, fitted or over sized, anything goes as long as you wear it with confidence.Pea Coat

Image Courtesy of VintageVixen.comYou don’t have to be a sailor to wear the across the board flattering pea coat. Though made in wool is most classic, designers have reinterpreted its shape in every fabric under the sun. Find one in your favorite color, or one in every color.
Khakis
Katherine Hepburn wore hers high and wide while the other famous Hepburn, Audrey, wore hers straight, snug and ankle bearing. It’s the khaki pant, and next to the jean it’s the most versatile pant for either sex. Luck for the ladies, over the years it has had more than nine lives so there are a variety of khaki styles to choose from.Trench Coat

Photo: shopgoodgrace.etsy.comStealing fashion from the opposite sex has been one of women’s best style ideas and the trench coat is the prefect example. A trench coat it looks great on everyone and you will look instantly put together in a trench; even if there’s just a smelly old sweat suit underneath. The mystery of what lies beneath a trench might just be why it has stuck around so long.