Breast self-exam is done once a month so that you become familiar with the usual appearance and feel of your own breasts. The best time to do a breast self-exam is two to three days after the end of your period, when your breasts are less likely to be tender or swollen.
If you discover anything unusual, such as lumps, discharge from the nipple or dimpling or puckering of the skin, you should see your doctor at once. Remember, eight out of 10 biopsied breast lumps are not cancer.