After breast reduction surgery, how would firm up my breasts?

No easy answer: Not sure what you mean by "firm up". Breast reduction is usually a very satisfying surgery for women that have long been bothered by disproportionately large, heavy and hanging breasts. It can be difficult to maintain fullness in the upper breast. Occasionally breast implants are indicated either at the same time or later. Restoring some of the lost volume may help.

Breast Implants?: Generally speaking, breast reduction surgery tends to be one of the most patient pleasing operations performed in the field of plastic surgery. Patient's' breasts end up lifted and smaller, but not “firmed up". Occasionally, patients will elect to undergo breast augmentation to increase firmness and/or volume of the upper chest wall/breast area.