Unfortunately, losing one's arms can be difficult, especially if a person's arms have been designed by his or her genes. There are a few things you can do to help shape your arms. (1) Working out with weights can help tighten up the muscles and fill out the arm if the skin is loose. (2) If there is still fat around your arms, keep exercising and reducing your caloric intake to lower the weight in your arms. I know these suggestions are not much but other than surgery, these are the best ways get your arms looking good.