They say you inherit your breast size from someone in your family. So in reality there is little you can do to correct their size, unless you plan to get them surgically enhanced. Various surveys have proved that women with the ideal breast size have higher self esteem.
There are many ways a woman can naturally enhance her breast size.
Here Few Tips For You:
Exercise:
Push-ups: Not only good for triceps, push-ups also help in strengthening the pectoral muscles that are located below the breasts. Initially, 
you may find this exercise a bit tiring, so start with 2 to 3 sets of ten push-ups in a day and increase the number as your body gets used to the exercise.
Crunches: Crunches trim the belly fat and strengthen ab muscles. Once the abs get in shape and toned, it strengthens breast muscles and you get fuller breasts. Lie on your back with your knees bent and feet flat on the floor. Place your hands under your head. 
Lift your shoulders and upper back up away from the floor. You eyes should be focused towards the ceiling. Exhale as you come up, hold for a second and inhale when you return to the original position.
Food:
Milk: Intake of milk contributes to the growth of breast tissues. Cowâs milk is enriched with estrogen, progesterone and prolactin, which are required to produce milk in women, thus enhancing breast size. 
Nuts: High in monosaturated fats, nuts are essential for building breast tissues and enhancing breast growth.
Green leafy vegetables: For bigger breasts, include green leafy vegetables in your daily diet. These vegetables are also a good source of iron and calcium. 
Mostly, green leafy vegetables do not contain phytoestrogens that help in increasing breast tissues, but they tone developed breasts. Another reason to eat green leafy vegetables is they prevent the male testosterone production in women. This balances the hormones in a womanâs body and allows natural estrogen level to control the body functioning.
Another way to get bigger breasts is massaging. Massage your breasts at least once a day. This increases blood circulation, which leads to a smooth flow of hormones and increases breast size.
