I'm very curious about this.
Iffy is right..............except one way is to gain some weight. Breast are fatty tissue. I've seen gals gain as little as 7 or 8 pounds and it usually goes to the boobs, thighs and butt first. (nothing wrong with that...........just one opinion)
There is no way to make your breasts larger besides getting pregnant or having surgery. Massaging will do nothing.
Yes, I have frequently been successful in obtaining a size increase whilst giving ladies a breast massage.
Yes, and getting fat. like onemandog said.