Vests have made a fashion resurgence in the last few years. Originally worn by men in a three-piece suit, vests are being embraced by the younger generation as a mixture of casual and formal dressing. Both men and women can embrace wearing a vest by pairing it with a casual T-shirt.
Pick your style of vest and T-shirt. This style is best achieved through simplicity. While there are many different patterned and colored vests and T-shirts, choose both in their most classic forms. A plain white, gray, black or navy V-neck T-shirt will offset the use of your vest as an accessory best. Your vest should be a dark color, either solid or with a simple, understated pin stripe.
Decide on the fit you want. A woman can wear the vest loose, a la the "boyfriend" trend, or fitted to show off her shape. The same rule applies to T-shirts. Men should wear both T-shirt and vest slightly fitted, as that is the most flattering and current trend.
Put on your T-shirt first, and then your vest over it. Style your look with accessories if you choose to do so. Wearing a necklace (for men and women) will draw attention to your chest. The more jewelry you wear, the more of a "rocker" and/or "biker" look you will achieve. Keeping jewelry to a minimum will keep the look classic and simple. Decide whether you want to button your vest or leave it open. A buttoned vest will show your shape. Not every button needs to be buttoned; one or two buttons will do just fine. An open vest is ultra casual. Tuck in your T-shirt or leave it hanging for a more casual look.