Can you massage your breasts to make them bigger?

Nope. There is very little you can do to increase breast size: weight gain can cause fat deposition throughout the body, including your cup size. Exercises that increase pectoral muscle mass (push ups, bench press) can create some definition, but do not increase cup size. Improving your posture can improve your silhouette significantly. Sit tall & be at peace: many large-breasted women wish to be small.