Buy the right one, not too tight or too loose. It is necessary to measure the chest circumference.

Third. Buy one without rims. As for the chest pad, feel free.

Fourth. Buy a buckle, or wear it directly, I-shape or neck, but don't wear a strapless bra.

Fifth. Buy developmental ones.

Six. Buy thirty or forty, it's too cheap, the material is not good and it's too expensive.

Seventh. Buy fine workmanship. If you don't want to itch in class, don't buy rough ones.

By the way

1. Don't wear it at night.

2. Wash and change frequently

If you don't want to be feasted by others because the school uniform is too thin in summer, buy some light colors, preferably white, and you can choose any color in winter.

If you wear dark colors in spring and autumn, you'd better wear a vest outside your underwear.

5. Bra with neck hanging, be careful to be pulled.

Ok, let's take it ┏ (ω) =?