Wearing a nice white tank top, t-shirt, dress shirt, or dress will always be in style. Nowadays you can forget the old rule that you can't wear white after Labour Day. What always will look tacky (unless you are a rockstar) is wearing a white bra underneath. Look at the photo on the left of the woman wearing a white bra under a white tank top. What specifically do you look at first? Personally my eye gravitates to her bust. If you don't want to advertise your bra and your bust and I think it's a faux paw to do so, then wear a skin coloured bra. This will provide you with a seamless look, so that your bra does not stand out under the shirt. If you are Caucasian, the best bra to wear with a white T-shirt is a beige bra. If you are darker skinned, your best bra choice under a white T-shirt is a chocolate one or even a black one, depending on your skin tone. This will minimize how noticeable the bra you are wearing is to others. Choose the same colour for your underpants when wearing white pants.