Fat lines and loose skin after slimming are very common problems. Here are some methods that may be useful:

-Keep your skin moist: Use moisturizing cream or oil to help keep your skin moist and reduce wrinkles and relaxation.

-Massage: Massage can promote blood circulation and increase the production of collagen and elastin, thus reducing wrinkles and relaxation.

-Exercise: Exercise can increase muscle mass, thus improving skin firmness.

-Diet adjustment: Eat more foods rich in collagen, vitamins C, E and zinc, such as fish, beans, nuts, fruits and vegetables.