There are two main ways to find breast changes:Clinical breast exam—a breast exam done by your health care provider Mammogram—an x-ray of your breasts
Some women check their own breasts for changes. If you find a change, it's important to see your health care provider. Make sure to watch the change you found until your appointment. But a breast self-exam and a clinical breast exam are not substitutes for mammograms.
This answer is based on source information from National Cancer Institute.