No great options
Other than surgically augmenting your breasts with implants or with your own fat, there is no reliable way to permanently "make your breasts grow larger and rounder." one system, brava (mybrava.
Com - I have not financial interest), uses a suction device worn >10 hours daily for 10-14 weeks and can give you a 1/2-2 cup increase. I believe the system must be used intermittently to maintain your gain.