How did Donald Trump avoid military service during the Vietnam War?

Donald Trump avoided military service during the Vietnam War through a series of deferments. Initially, he qualified for four educational deferments while attending an Ivy League school where he studied economics and business. These deferments exempted him from the draft while he was in college. After graduating from college, when he would have become eligible for military service, Trump obtained another deferment due to a medical condition - specifically, a problem with his heel bone. This heel spur diagnosis provided him with the medical exemption needed to avoid being drafted into service during the Vietnam conflict.