Hello sister! Even though it is an A cup, you still need to wear underwear. This can also increase your curves and avoid embarrassment. There are many A-cup push-up bras on the market today that can improve breast shape. There is also an adjustable camisole (with built-in thin layer of underwear) that is very comfortable to wear. In addition to external modifications, you should also increase nutrition and make yourself fatter. The human body has proportions. If you are too thin, there will be no flesh anywhere! Another thing is to do breast expansion exercises regularly to stimulate secondary growth. Hope this helps!